Diagnostic lookup
Garage door opener error code finder
Search the exact code or light pattern you can see. Published records are tied to manufacturer guidance through their full troubleshooting guides.
SOURCE-VERIFIED DATASET
1-2LiftMaster / Chamberlain
Safety sensor wiring issue
↑1UP flashes
then↓2DOWN flashes
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The opener detected shorted or reversed safety-sensor wiring.
Next checks
- Inspect sensor wire for cuts or staples
- Check loose terminals
- Make sure bare copper is not touching
4-1LiftMaster / Chamberlain
Unexpected RPM / motor-current change during DOWN travel
↑4UP flashes
then↓1DOWN flashes
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Chamberlain Group’s detailed diagnostic table defines 4-1 as an unforeseen RPM or DC-motor-current change while the door is traveling down.
Next checks
- Stop repeated cycles
- Check door path for binding
- Compare manual door movement safely
10 flashesChamberlain / LiftMaster (affected models)
Safety-reversing sensor symptom
10 flashescount the repeating signal before the pause
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
On affected models, ten opener-light flashes commonly point to a safety-sensor issue.
Failure familySafety Beam Obstruction, Alignment & InterferenceFailure familySafety Sensor Wiring, Power & Hardware
Next checks
- Remove beam obstruction
- Check both sensor LEDs
- Inspect alignment and low-voltage wiring
2 red blinks + green ONGenie Safe-T-Beam
Beam alignment / obstruction / sensor issue
Red source2 blinks
Green receiveron
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie lists beam misalignment, obstruction or a defective sensor as possible causes.
Next checks
- Clean lenses
- Remove obstruction
- Re-align sensors
2 red blinks + green OFFGenie Safe-T-Beam
Sensor wiring / sensor issue
Red source2 blinks
Green receiveroff
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie lists missing/bad sensor wiring or a defective sensor as possible causes.
Next checks
- Inspect sensor wiring
- Check opener terminals
- Check sensor housing
3 red blinks + green ONGenie Safe-T-Beam
Sensor interference
Red source3 blinks
Green receiveron
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie identifies interference at the sensor as the likely branch.
Next checks
- Look for nearby light/interference sources
- Re-check sensor aim
- Test after removing the suspected source
4 red blinks + green ONGenie Safe-T-Beam
Source not sending pulses / source fault
Red source4 blinks
Green receiveron
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie points to the source not sending pulses or a defective source unit.
Next checks
- Verify wiring and power
- Inspect source sensor
- Use Genie support if the pattern persists
4-2LiftMaster / Chamberlain
Excessive opening force detected
↑4UP flashes
then↓2DOWN flashes
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The operator detected too much force while trying to open the garage door.
Next checks
- Stop repeated cycles
- Check for binding or obstruction
- Use dealer/model-specific diagnosis if the door moves normally
4-3LiftMaster / Chamberlain
Motor power / RPM loss detected
↑4UP flashes
then↓3DOWN flashes
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The operator detected loss of motor RPM while trying to close; Chamberlain Group lists travel-module connections as a possible cause.
Next checks
- Record reversal point
- Rule out obvious mechanical binding
- Escalate internal module/wiring diagnosis
4-5LiftMaster / Chamberlain
Unrecognized travel module
↑4UP flashes
then↓5DOWN flashes
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The operator does not recognize the installed travel module.
Next checks
- Note recent opener service
- Record opener model and module part number
- Verify the correct travel module
4-6LiftMaster / Chamberlain
Safety sensors obstructed or not aligned
↑4UP flashes
then↓6DOWN flashes
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The operator detected a blocked or misaligned safety-sensor condition during closing.
Next checks
- Clear the beam
- Read both sensor LEDs
- Align sensors and test safety reversal
red OFF + green OFFGenie Safe-T-Beam
Powerhead power / wiring from powerhead
Redoff
+Greenoff
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
With both Safe-T-Beam LEDs off, Genie points to an unpowered powerhead or bad wiring from the powerhead.
Next checks
- Confirm opener power
- Inspect visible sensor-circuit wiring
- Check for obvious shorts or loose terminals
red OFF + green ONGenie Safe-T-Beam
Source wiring / power interruption
Redoff
+Greenon
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie lists missing or bad wiring to the source or a recent power interruption for this LED pair.
Next checks
- Identify red source unit
- Inspect source wiring
- Reapply normal opener power and observe LEDs
red ON + green ONGenie Safe-T-Beam
Normal Safe-T-Beam state
Redon
+Greenon
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Solid red and solid green indicate normal Safe-T-Beam operation; a remaining closing fault belongs in another diagnostic branch.
Next checks
- Confirm LEDs remain steady during operation
- Perform the safety reversal test
- Move to model-specific opener diagnostics if the test passes
1-1LiftMaster / Chamberlain
Safety sensors blocked, misaligned or disconnected
↑1UP flashes
then↓1DOWN flashes
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The opener detects a safety-sensor obstruction, alignment, connection or wiring issue.
Failure familySafety Beam Obstruction, Alignment & InterferenceFailure familySafety Sensor Wiring, Power & Hardware
Next checks
- Clear the beam
- Read both sensor LEDs
- Check alignment and low-voltage connections
amber OFF + green OFFChamberlain / LiftMaster sensors
Both safety-sensor LEDs off
Amberoff
+Greenoff
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Chamberlain points to missing/disconnected sensors, short/broken wiring, or a faulty sensor for this state.
Next checks
- Confirm sensors are connected
- Inspect opener terminals
- Check visible wire for shorts or breaks
amber ON + green OFFChamberlain / LiftMaster sensors
Receiving-sensor wiring issue
Amberon
+Greenoff
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The amber sender is powered, while the green receiver side has a wiring/connection problem in Chamberlain's LED table.
Next checks
- Check green receiver alignment
- Inspect receiver wiring
- Verify low-voltage terminal connection
green LED blinkingChamberlain / LiftMaster sensors
Sensors misaligned or obstructed
green LED blinking
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Chamberlain maps a blinking green receiving LED to misalignment or obstruction, with wiring checks if it will not stabilize.
Next checks
- Clear beam
- Align green receiver
- Inspect wiring if LED remains unstable
amber ON + green ONChamberlain / LiftMaster sensors
Sensors aligned / normal state
Amberon
+Greenon
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Both LEDs solid means the sensors are aligned; a remaining closing problem belongs in another diagnostic branch.
Next checks
- Confirm LEDs stay solid
- Test safety reversal
- Record the opener's next symptom or code
1-3LiftMaster / Chamberlain
Wall control wire short
↑1UP flashes
then↓3DOWN flashes
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The opener detected a short in the low-voltage wires between the wall control and the garage door opener; remotes/keypad can still work while the wall control does not.
Next checks
- Confirm remote/keypad still works
- Inspect red/white control-wire terminations
- Look for staples, screws or exposed copper shorting the control cable
1-5LiftMaster / Chamberlain
No RPM detected at startup
↑1UP flashes
then↓5DOWN flashes
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The opener detected no RPM during the first second of movement; diagnosis branches by whether the door moves a few inches, hums, or only clicks.
Failure familyMechanical Resistance & Force DetectionFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Record exact startup sound/movement
- Check safe manual door movement
- Verify release/trolley engagement for the exact opener type
3-5LiftMaster / Chamberlain RJO
Cable Tension Monitor tripped or not detected
↑3UP flashes
then↓5DOWN flashes
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
On applicable jackshaft/wall-mount systems, the opener is not seeing a normal Cable Tension Monitor condition.
Next checks
- Confirm exact RJO model
- Inspect monitor position and low-voltage wire
- Do not adjust tensioned garage-door cables
4-4LiftMaster / Chamberlain
Loss of RPM during UP travel
↑4UP flashes
then↓4DOWN flashes
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The opener detected loss of motor RPM while opening; Chamberlain Group lists travel-module connection issues and an RJO emergency-release state as documented branches.
Next checks
- Confirm failure occurs during opening
- Check safe manual door movement
- On RJO units, verify the emergency release is reconnected per the manual
5-5LiftMaster / Chamberlain
Unattended command / myQ remote light requirement
↑5UP flashes
then↓5DOWN flashes
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
On applicable systems, an unattended open/close command was received but the required myQ Remote/Smart LED Light is not installed or programmed.
Next checks
- Confirm exact opener applicability
- Check that the failure is specific to unattended control
- Verify the remote light is powered and paired
1-4LiftMaster / Chamberlain
Brief safety-sensor obstruction / misalignment
↑1UP flashes
then↓4DOWN flashes
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The safety sensors were obstructed or misaligned for less than four seconds.
Next checks
- Clear the beam
- Check for a slightly flickering green receiver LED
- Re-align if the receiver is not solid
1-6LiftMaster / Chamberlain
RPM detected after motor shutoff at open position
↑1UP flashes
then↓6DOWN flashes
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
RPM was detected after the motor stopped at the open position; RJO manual operation can also produce this code.
Next checks
- Note recent manual-release use
- Check door balance safely
- Verify the manual release is reconnected
2-1LiftMaster / Chamberlain
Logic-board component failure
↑2UP flashes
then↓1DOWN flashes
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Chamberlain Group groups 2-1 through 2-5 as logic-board component failures.
Next checks
- Record exact model/code
- Power-cycle AC and battery if applicable
- If persistent, verify board/service path
2-2LiftMaster / Chamberlain
Logic-board component failure
↑2UP flashes
then↓2DOWN flashes
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Chamberlain Group groups 2-1 through 2-5 as logic-board component failures.
Next checks
- Record exact model/code
- Power-cycle AC and battery if applicable
- If persistent, verify board/service path
2-3LiftMaster / Chamberlain
Logic-board component failure
↑2UP flashes
then↓3DOWN flashes
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Chamberlain Group groups 2-1 through 2-5 as logic-board component failures.
Next checks
- Record exact model/code
- Power-cycle AC and battery if applicable
- If persistent, verify board/service path
2-4LiftMaster / Chamberlain
Logic-board component failure
↑2UP flashes
then↓4DOWN flashes
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Chamberlain Group groups 2-1 through 2-5 as logic-board component failures.
Next checks
- Record exact model/code
- Power-cycle the opener
- If persistent, verify board/service path
2-5LiftMaster / Chamberlain
Logic-board component failure
↑2UP flashes
then↓5DOWN flashes
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Chamberlain Group groups 2-1 through 2-5 as logic-board component failures.
Next checks
- Record exact model/code
- Power-cycle the opener
- If persistent, verify board/service path
3-2LiftMaster / Chamberlain
Power loss / travel-position recovery
↑3UP flashes
then↓2DOWN flashes
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The opener lost power and needs to locate its travel position.
Next checks
- Confirm stable outlet power
- Run one supervised open/close cycle
- Use myQ diagnostics if the error remains
3-3LiftMaster / Chamberlain
Logic-board / battery over-voltage condition
↑3UP flashes
then↓3DOWN flashes
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The operator detected a logic-board problem; the detailed table also reports battery over-voltage on applicable models.
Next checks
- Record battery indicator behavior
- Power-cycle AC/battery as documented
- Escalate persistent code to board/service diagnosis
powerhead RED solidGenie 1022/1024/1042/2022/2024/2042/2027
Programming incomplete
LEDpowerhead RED solid
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie says a continuously ON red powerhead diagnostic LED means required programming is incomplete on this model family.
Next checks
- Confirm exact model and powerhead LED
- Check travel/limit programming
- Complete only the required model-specific setup
powerhead RED 1 blinkGenie 1022/1024/1042/2022/2024/2042/2027
Transmitter has not learned
powerhead RED 1 blinkcount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie says one red powerhead blink followed by a pause means the transmitter has not learned into receiver memory.
Next checks
- Compare wall-control vs remote operation
- Verify remote compatibility
- Program one known-compatible remote
powerhead GREEN 3 blinksGenie 1022/1024/1042/2022/2024/2042/2027
Travel limits set backwards
powerhead GREEN 3 blinkscount the repeating signal before the pause
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie says three green powerhead blinks mean the travel limits are set backwards.
Next checks
- Confirm model family
- Clear limits using exact instructions
- Program DOWN then UP limits
powerhead GREEN 4 blinksGenie 1022/1024/1042/2022/2024/2042/2027
Wall-button wire short or reversed
powerhead GREEN 4 blinkscount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie says four green powerhead blinks mean the wall-button wire is shorted or the wall-button wires are reversed.
Next checks
- Compare wall and remote controls
- Inspect low-voltage wall-control cable
- Verify terminal orientation
powerhead GREEN 5 blinksGenie 1022/1024/1042/2022/2024/2042/2027
Chain/belt too tight or control-system failure
powerhead GREEN 5 blinkscount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie lists excessive chain/belt tension or a control-system failure for five green powerhead blinks on this model family.
Failure familyMechanical Resistance & Force DetectionFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Confirm exact five-blink pattern
- Check exact-manual drive tension
- Separate door binding from internal control failure
4 blinksGenie Excelerator
Force settings incorrect
4 blinkscount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie says four repeating Excelerator status-light blinks mean the force settings are incorrect and the garage door condition should also be checked.
Next checks
- Confirm Excelerator model family
- Check safe door condition
- Compare force setting with exact manual
5 blinksGenie Excelerator
Safe-T-Beam malfunction
5 blinkscount the repeating signal before the pause
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie says five repeating Excelerator status-light blinks mean a Safe-T-Beam malfunction.
Failure familySafety Beam Obstruction, Alignment & InterferenceFailure familySafety Sensor Wiring, Power & Hardware
Next checks
- Read both Safe-T-Beam LEDs
- Clear beam and verify alignment
- Inspect accessible sensor wiring
6 blinksGenie Excelerator
Wall console does not work
6 blinkscount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie says six repeating Excelerator status-light blinks mean the wall console does not work; check shorts, tight staples, pinched wire and connections.
Next checks
- Compare remote vs wall-console operation
- Inspect low-voltage wall-control wire
- Verify powerhead and console connections
7 blinksGenie Excelerator
Limit switches not working
7 blinkscount the repeating signal before the pause
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie says seven repeating Excelerator status-light blinks mean the limit switches are not working.
Next checks
- Confirm Excelerator family
- Check limit-switch terminal connections
- Inspect for pinched/shorted switch wires
8 blinksGenie Excelerator
Wall console locked / vacation lock
8 blinkscount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie says eight repeating Excelerator status-light blinks mean the vacation locking switch on the wall control is in Lock mode.
Next checks
- Check Sure-Lock/vacation switch
- Unlock before reprogramming remotes
- Verify wall-console state and wiring if it will not clear
1 blinkGenie Excelerator
Motor drive board interrupt
1 blinkcount the repeating signal before the pause
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie defines one repeating Excelerator status-light blink as a motor drive board interrupt and says a recurring signal can also be caused by abnormal garage-door balance or binding load.
Failure familyOperator Electronics, Control Board & Thermal ProtectionFailure familyMechanical Resistance & Force Detection
Next checks
- Use the five-second manufacturer reset once
- Check safe garage-door condition if the code recurs
- Escalate persistent internal electronics diagnosis
2 blinksGenie Excelerator
Controller board interrupt
2 blinkscount the repeating signal before the pause
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie defines two repeating Excelerator status-light blinks as a controller board interrupt.
Next checks
- Use the five-second manufacturer reset once
- Record whether normal operation returns
- Escalate persistent board/interconnect diagnosis
3 blinksGenie Excelerator
Overheated or over-cycled
3 blinkscount the repeating signal before the pause
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie says three repeating Excelerator status-light blinks mean the opener is overheated or over-cycled and instructs owners not to disconnect power while cycle allowance recovers.
Next checks
- Leave power connected
- Wait about 10 minutes without cycling
- Record recurrence during ordinary use
powerhead GREEN 1 blinkGenie 1022/1024/1042/2022/2024/2042/2027
Limits / beam obstruction / door obstruction
powerhead GREEN 1 blinkcount the repeating signal before the pause
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie lists incomplete limit programming, a Safe-T-Beam obstruction while closing, or a door obstruction opening/closing for one green powerhead blink on this model family.
Failure familyTravel, Limit & Position SetupFailure familySafety Beam Obstruction, Alignment & InterferenceFailure familyMechanical Resistance & Force Detection
Next checks
- Check recent limit-programming history
- Read Safe-T-Beam LEDs during closing
- Check safe manual door condition
powerhead GREEN 2 blinksGenie 1022/1024/1042/2022/2024/2042/2027
UP limit / wiring / Safe-T-Beam branch
powerhead GREEN 2 blinkscount the repeating signal before the pause
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Genie lists incomplete UP-limit programming, a bad wire/connection at the powerhead, sensor misalignment, or continuous Safe-T-Beam obstruction for two green powerhead blinks.
Failure familyTravel, Limit & Position SetupFailure familySafety Beam Obstruction, Alignment & InterferenceFailure familySafety Sensor Wiring, Power & Hardware
Next checks
- Verify UP-limit setup
- Read Safe-T-Beam LED pair
- Inspect accessible low-voltage wiring/connections
5 flashesLiftMaster 2500B/2500D/3500/3850
No RPM detected during first second
5 flashescount the repeating signal before the pause
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The legacy DC diagnostic chart identifies no RPM detection during the first second of operation.
Failure familyOperator Electronics, Control Board & Thermal ProtectionFailure familyMechanical Resistance & Force Detection
Next checks
- Confirm exact model family
- Record movement distance and sound
- Check safe door condition before internal diagnosis
6 flashesLiftMaster 2500B/2500D/3500/3850
RPM detected after motor commanded off
6 flashescount the repeating signal before the pause
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The legacy DC diagnostic chart identifies RPM feedback after the motor is commanded off, consistent with a coasting/feedback branch.
Failure familyOperator Electronics, Control Board & Thermal ProtectionFailure familyMechanical Resistance & Force Detection
Next checks
- Confirm exact model family
- Record whether the door/opener coasts
- Stop if door mechanics are abnormal
7 flashesLiftMaster 2500B/2500D/3500/3850
Motor short / no movement or sound
7 flashescount the repeating signal before the pause
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The legacy DC chart assigns seven flashes to the motor-short branch with no movement and no sound.
Next checks
- Confirm exact model family
- Record no-movement/no-sound state
- Escalate internal motor/electrical diagnosis
10 flashesLiftMaster 2500B/2500D/3500/3850
Force reversal during UP travel
10 flashescount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The legacy DC chart identifies a force-reversal condition while the door is opening.
Next checks
- Record UP-travel failure
- Check for obstruction/binding
- Do not raise force to mask a heavy door
11 flashesLiftMaster 2500B/2500D/3500/3850
Maximum force during DOWN travel
11 flashescount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The legacy DC chart identifies a maximum-force condition during closing; the door can stop and reverse.
Next checks
- Record DOWN-travel failure
- Check door path and safe movement
- Use model-specific force/travel procedure only after mechanics are normal
12 flashesLiftMaster 2500B/2500D/3500/3850
Force reversal during DOWN travel
12 flashescount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The legacy DC chart identifies a force-reversal condition during closing; the door can stop and reverse.
Next checks
- Record DOWN-travel failure
- Check obstruction and door condition
- Keep force adjustment model-specific
13 flashesLiftMaster 2500B/2500D/3500/3850
Maximum force during UP travel
13 flashescount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The legacy DC chart identifies a maximum-force condition while opening.
Next checks
- Record UP-travel failure
- Check for binding/heavy door
- Stop if spring/cable/track condition is abnormal
15 flashesLiftMaster 2500B/2500D/3500/3850
Bad CRC / internal electronics branch
15 flashescount the repeating signal before the pause
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The legacy DC chart defines 15 flashes as Bad CRC and describes no movement/no sound.
Next checks
- Confirm exact model and 15-flash pattern
- Verify accessible power facts
- Use exact-model board/service verification
1 flashCraftsman — legacy Learn LED
Safety-sensor wiring open, broken or disconnected
LED1 flash
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
On exact-model shared 1–6 charts such as Craftsman 139.53914D and 139.53985DM, one diagnostic-LED flash points to an open, broken or disconnected safety-sensor circuit.
Failure familySafety Beam Obstruction, Alignment & InterferenceFailure familySafety Sensor Wiring, Power & Hardware
Next checks
- Confirm the exact model uses the shared 1–6 chart
- Read both safety-sensor LEDs
- Inspect accessible low-voltage sensor wiring for breaks or loose connections
2 flashesCraftsman — legacy Learn LED
Safety-sensor wires shorted or reversed
2 flashescount the repeating signal before the pause
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps two flashes to shorted safety-sensor wires or sensor wires reversed at the logic-board terminals.
Next checks
- Confirm the exact model uses the shared 1–6 chart
- Inspect visible sensor wire for crushed insulation or exposed copper
- Verify sensor-wire terminal placement against the exact manual
3 flashesCraftsman — legacy Learn LED
Wall-control wires shorted
3 flashescount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps three flashes to a short in the low-voltage wiring between the wall-mounted door control and the opener.
Next checks
- Confirm the exact model uses the shared 1–6 chart
- Inspect the wall-control cable for staples, cuts or exposed conductors
- Check accessible low-voltage terminations before replacing the control
4 flashesCraftsman — legacy Learn LED
Safety sensors slightly misaligned
4 flashescount the repeating signal before the pause
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps four flashes on the shared legacy chart to safety-reversing sensors that are slightly misaligned.
Next checks
- Confirm the exact model uses the shared 1–6 chart
- Clear the beam and read both sensor LEDs
- Align the receiving sensor only with the door stationary and doorway clear
5 flashesCraftsman — legacy Learn LED
Motor overheated / excessive load branch
5 flashescount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps five flashes to an overheated motor. Repeated cycling or a door that does not travel smoothly can overload the opener, so door condition belongs ahead of motor replacement.
Failure familyMechanical Resistance & Force DetectionFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Confirm the exact model uses the shared 1–6 chart
- Allow the opener to cool before another test
- Check safe manual door movement and stop for a heavy or binding door
6 flashesCraftsman — legacy Learn LED
Motor circuit / logic-board branch
6 flashescount the repeating signal before the pause
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps six flashes on the shared legacy chart to a motor-circuit failure and directs repair toward the logic-board path after model-specific confirmation.
Next checks
- Confirm the exact model uses the shared 1–6 chart
- Record whether the opener makes any motor sound or movement
- Escalate internal electrical diagnosis rather than repeated resets
1 flashCraftsman — 139.53918D exact chart
Safety-sensor circuit open, broken or disconnected
LED1 flash
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The Sears 139.53918D owner manual REV F maps one Learn-button diagnostic flash to an open safety-reversing-sensor circuit: broken or disconnected wiring.
Next checks
- Confirm the motor-unit label is exactly 139.53918D
- Read both safety-sensor LEDs
- Inspect accessible low-voltage sensor wiring for a break or loose connection
2 flashesCraftsman — 139.53918D exact chart
Safety-sensor wiring shorted or reversed
2 flashescount the repeating signal before the pause
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact REV F chart maps two flashes to shorted safety-sensor wiring or black/white sensor wires reversed.
Next checks
- Confirm exact model 139.53918D
- Inspect visible sensor wiring for damaged insulation or exposed copper
- Verify low-voltage sensor-wire polarity against the exact manual
3 flashesCraftsman — 139.53918D exact chart
Door control or door-control wiring shorted
3 flashescount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact 139.53918D REV F diagnostic chart maps three flashes to the wired door-control circuit rather than the handheld-remote radio path.
Next checks
- Confirm exact model 139.53918D
- Inspect accessible wall-control wiring for staples, cuts or exposed conductors
- Keep wall-control diagnosis separate from remote compatibility
4 flashesCraftsman — 139.53918D exact chart
Safety sensors slightly misaligned
4 flashescount the repeating signal before the pause
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact REV F chart maps four flashes to slightly misaligned safety reversing sensors, typically with a dim or flashing receiving-eye indicator.
Next checks
- Confirm exact model 139.53918D
- Clear the photo-eye beam and clean the lenses
- Align the receiving sensor with the door stationary and verify the track is secure
5 flashesCraftsman — 139.53918D exact chart
Motor RPM not recognized — split by motion symptom
5 flashescount the repeating signal before the pause
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The Sears 139.53918D owner manual REV F labels five flashes 'Motor RPM is not recognized.' Its next step depends on the motion fingerprint: about 2–3 inches of travel routes through limits/force and the travel-module connection, while a motor that runs briefly with no normal movement routes through the emergency-release connection and then motor service.
Failure familyTravel, Limit & Position SetupFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Record whether the opener travels about 2–3 inches or only runs briefly without door movement
- Check safe door condition before any force/travel procedure
- Use the exact REV F branch; do not import a generic sixth-flash or different five-flash meaning from another Craftsman manual
1-1Craftsman — DC UP/DOWN arrows
Safety sensors missing, disconnected or wiring broken
↑1UP flashes
then↓1DOWN flashes
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 1-UP/1-DOWN to safety sensors that are not installed or connected, or to broken sensor wiring.
Next checks
- Confirm the opener uses UP/DOWN arrow diagnostics
- Check both sensor connections at the motor unit
- Inspect accessible sensor wiring for breaks
1-2Craftsman — DC UP/DOWN arrows
Safety-sensor wires shorted or reversed
↑1UP flashes
then↓2DOWN flashes
Strongest current branchSafety Sensor Wiring, Power & Hardware
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 1-UP/2-DOWN to safety-sensor wiring that is shorted or reversed.
Next checks
- Confirm the opener uses UP/DOWN arrow diagnostics
- Verify sensor-wire polarity/terminal placement
- Inspect accessible wiring for damage or exposed conductors
1-3Craftsman — DC UP/DOWN arrows
Wall control defective or wall-control wiring broken
↑1UP flashes
then↓3DOWN flashes
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 1-UP/3-DOWN to a defective wall control or broken wall-control wiring.
Next checks
- Confirm the opener uses UP/DOWN arrow diagnostics
- Inspect accessible wall-control wiring and terminations
- Keep the low-voltage wall-control branch separate from the handheld-radio branch
1-4Craftsman — DC UP/DOWN arrows
Safety sensors misaligned or obstructed
↑1UP flashes
then↓4DOWN flashes
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 1-UP/4-DOWN to safety sensors that are misaligned or obstructed.
Next checks
- Confirm the opener uses UP/DOWN arrow diagnostics
- Clear the beam path
- Align sensors with the door stationary and confirm both LEDs are normal
1-5Craftsman — DC UP/DOWN arrows
Logic-board or travel-module branch
↑1UP flashes
then↓5DOWN flashes
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 1-UP/5-DOWN to a defective logic board or travel module, with wiring between those components checked before replacement.
Failure familyTravel, Limit & Position SetupFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Confirm the opener uses UP/DOWN arrow diagnostics
- Record whether the door moves only a short distance before stopping
- Escalate internal travel-module/logic-board diagnosis after accessible door checks
3-3Craftsman — DC UP/DOWN arrows
Logic-board failure branch
↑3UP flashes
then↓3DOWN flashes
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 3-UP/3-DOWN to a defective logic board.
Next checks
- Confirm the opener uses UP/DOWN arrow diagnostics
- Record the exact repeating pair before removing power
- Use exact-model service/parts evidence for internal electronics
4-1Craftsman — DC UP/DOWN arrows
Door binding or obstruction while closing
↑4UP flashes
then↓1DOWN flashes
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 4-UP/1-DOWN to a garage door binding on the tracks or encountering an obstruction while closing.
Next checks
- Confirm failure occurs during closing
- Remove visible obstruction and inspect the tracks
- Check safe manual door movement and stop for abnormal resistance
4-2Craftsman — DC UP/DOWN arrows
Door binding while opening
↑4UP flashes
then↓2DOWN flashes
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 4-UP/2-DOWN to garage-door binding while opening.
Next checks
- Confirm failure occurs during opening
- Check that any manual door lock is released
- Inspect tracks/door movement and stop for a heavy or binding door
4-3Craftsman — DC UP/DOWN arrows
Door binding or travel limits not set correctly
↑4UP flashes
then↓3DOWN flashes
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 4-UP/3-DOWN to garage-door binding or travel limits that are not set properly.
Next checks
- Check door movement before reprogramming travel
- Record whether the opener stops short or overruns
- Use the exact model's electronic travel procedure only after mechanics are normal
4-4Craftsman — DC UP/DOWN arrows
Door binding or hitting an obstruction
↑4UP flashes
then↓4DOWN flashes
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 4-UP/4-DOWN to a door that is binding or hitting an obstruction.
Next checks
- Remove visible obstruction
- Inspect tracks and door path
- Check safe manual door movement before opener adjustments
4-5Craftsman — DC UP/DOWN arrows
Travel-module / logic-board communication error
↑4UP flashes
then↓5DOWN flashes
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 4-UP/5-DOWN to a communication error between the travel module and logic board.
Failure familyTravel, Limit & Position SetupFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Confirm the opener uses UP/DOWN arrow diagnostics
- Preserve the code before power removal
- Use exact-model service guidance for internal wiring/travel-module diagnosis
4-6Craftsman — DC UP/DOWN arrows
Safety sensors temporarily obstructed or misaligned
↑4UP flashes
then↓6DOWN flashes
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Sears maps 4-UP/6-DOWN to safety sensors that are temporarily obstructed or misaligned; rail vibration and sunlight can also disturb the beam.
Next checks
- Clear and align the sensor beam
- Observe whether rail vibration changes sensor alignment
- Check for direct sunlight/interference before replacing sensors
7Marantec — Synergy numeric display
Programming/reference-point notice
LED7
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The verified Synergy manuals associate code 7 with programming timing/reference-point conditions rather than a normal door-travel component diagnosis.
Next checks
- Confirm the exact Synergy model/manual family
- Record what was being programmed when the code appeared
- Use the exact setup procedure rather than repeating random adjustments
8Marantec — Synergy numeric display
Adjustment interrupted / reference-switch branch
LED8
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Marantec maps code 8 to an adjustment sequence interrupted before completion and/or a defective reference-switch branch.
Failure familyTravel, Limit & Position SetupFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Confirm setup was completed without interruption
- Preserve the code if normal operation is not restored
- Escalate reference-switch service rather than guessing at force settings
9Marantec — Synergy numeric display
RPM sensor impulse absent / operator obstructed
LED9
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Marantec identifies code 9 with a missing RPM-sensor impulse or an obstructed operator-system branch.
Failure familyOperator Electronics, Control Board & Thermal ProtectionFailure familyMechanical Resistance & Force Detection
Next checks
- Check for obvious door-path obstruction
- Record whether the motor starts or the door moves
- Use service support for persistent RPM-sensor diagnosis
10Marantec — Synergy numeric display
Door difficult/obstructed or driving-power branch
LED10
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The Synergy table places code 10 in a difficult or obstructed door-movement / driving-power branch.
Next checks
- Remove obvious obstruction
- Check safe manual door movement
- Do not raise force to compensate for a heavy or binding door
11Marantec — Synergy numeric display
Maximum run-time limit exceeded
LED11
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Marantec maps code 11 to the operator exceeding its maximum run-time limit.
Next checks
- Record where travel stops
- Check that the rail/drive moves normally
- Stop for abnormal resistance or a mechanically unsafe door
15Marantec — Synergy numeric display
Photo-eye connection, alignment or obstruction
LED15
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Marantec maps code 15 to photo eyes that are not connected/aligned or to an obstruction breaking the photo-eye beam.
Failure familySafety Beam Obstruction, Alignment & InterferenceFailure familySafety Sensor Wiring, Power & Hardware
Next checks
- Clear the photo-eye beam
- Check sensor alignment
- Inspect accessible low-voltage photo-eye wiring and terminals
16Marantec — Synergy numeric display
Motor-overload current-sensor branch
LED16
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The Synergy troubleshooting table places code 16 in the motor-overload/current-sensor branch and directs persistent faults to service.
Next checks
- Stop repeated cycling
- Record the exact code and movement symptom
- Use authorized service for current-sensor/internal diagnosis
26Marantec — Synergy numeric display
Power overload condition
LED26
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Marantec identifies code 26 as a power-overload condition in the operator system.
Next checks
- Stop repeated cycles
- Check normal supply power without opening the operator
- Escalate persistent overload diagnosis
28Marantec — Synergy numeric display
Stiff/irregular/blocked door or sensitivity branch
LED28
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Marantec maps code 28 to stiff or irregular door movement, a blocked door, or operating sensitivity set too low/sensitive.
Next checks
- Remove obvious obstruction
- Check safe manual door movement
- Have sensitivity/force settings checked only after door mechanics are normal
30Marantec — Synergy numeric display
MS-Bus communication fault
LED30
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The verified Synergy table identifies code 30 as an MS-Bus fault.
Next checks
- Record the exact model and code
- Note any recently changed control/accessory
- Use model-specific service for bus/electronics diagnosis
35Marantec — Synergy numeric display
Electronic defect
LED35
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Marantec identifies code 35 as an electronic defect and directs the operator to service.
Next checks
- Preserve the code before power removal
- Avoid repeated resets
- Use authorized/model-specific electronics service
36Marantec — Synergy numeric display
Wall control connected incorrectly
LED36
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
Marantec maps code 36 to an incorrectly connected wall control and calls for checking wall-control terminal connections, then resetting the operator.
Next checks
- Inspect accessible wall-control terminal placement
- Check low-voltage wiring for obvious loose or crossed conductors
- Reset only after the connection is verified
7Marantec — M55 numeric display
Programming/reference-point notice
LED7
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact M55 table associates code 7 with programming timing/reference-point conditions rather than a normal component-failure verdict.
Next checks
- Confirm the opener is M55
- Record what programming step was underway
- Use the exact M55 setup procedure rather than random adjustments
8Marantec — M55 numeric display
Adjustment interrupted / reference-switch branch
LED8
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The M55 troubleshooting table maps code 8 to an adjustment sequence interrupted before completion and/or a defective reference-switch branch.
Failure familyTravel, Limit & Position SetupFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Confirm whether setup was interrupted
- Preserve the code if normal operation is not restored
- Use professional service for a persistent reference-switch fault
9Marantec — M55 numeric display
Rotational-speed/RPM impulse absent or operator obstructed
LED9
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact M55 table places code 9 in the missing speed-sensor impulse / obstructed operator-system branch.
Failure familyOperator Electronics, Control Board & Thermal ProtectionFailure familyMechanical Resistance & Force Detection
Next checks
- Check for obvious door-path obstruction
- Record whether the motor starts or the door moves
- Use service support for persistent speed-sensor/internal diagnosis
10Marantec — M55 numeric display
Door difficult/obstructed or driving-power branch
LED10
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact M55 table maps code 10 to a door that does not move easily or is obstructed and/or a maximum-driving-power setting branch.
Next checks
- Remove obvious obstruction
- Check safe manual door movement
- Do not raise force to compensate for a heavy or binding door
11Marantec — M55 numeric display
Maximum run-time / excess-travel branch
LED11
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The M55 troubleshooting table places code 11 in the excess-travel / maximum-run-time branch.
Next checks
- Record where travel stops
- Check that the rail/drive moves normally without internal disassembly
- Stop for abnormal resistance or a mechanically unsafe door
15Marantec — M55 numeric display
Photo eyes disconnected, misaligned or obstructed
LED15
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact M55 table maps code 15 to photo-eye connection, alignment or beam-obstruction trouble.
Failure familySafety Beam Obstruction, Alignment & InterferenceFailure familySafety Sensor Wiring, Power & Hardware
Next checks
- Clear the photo-eye beam
- Check sensor alignment
- Inspect accessible low-voltage sensor wiring and terminals
16Marantec — M55 numeric display
Automatic cut-out current-sensor fault
LED16
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact M55 table identifies code 16 with a defective current sensor for the automatic cut-out and directs the operator to service.
Next checks
- Stop repeated cycling
- Record the exact code and movement symptom
- Use professional service for current-sensor/internal diagnosis
26Marantec — M55 numeric display
Operator overload / supplied-power branch
LED26
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The M55 table identifies code 26 with operator overload and directs the supplied-power/outlet branch to be checked.
Next checks
- Stop repeated cycles
- Verify normal outlet power externally
- Escalate persistent overload or supply-power diagnosis
28Marantec — M55 numeric display
Stiff/irregular/blocked door or sensitivity branch
LED28
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact M55 table maps code 28 to stiff or irregular door movement, a blocked door, or operating sensitivity set too sensitive/low.
Next checks
- Remove obvious obstruction
- Check safe manual door movement
- Leave sensitivity adjustment to the professional procedure after door mechanics are normal
30Marantec — M55 numeric display
MS-Bus fault
LED30
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact M55 table identifies code 30 as an MS-Bus fault and routes the connected bus-module branch to service checks.
Next checks
- Record the exact model and code
- Note any recently changed control/accessory
- Use model-specific service for bus/module diagnosis
33Marantec — M55 numeric display
Rise in temperature
LED33
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact M55 troubleshooting table identifies code 33 as a rise in temperature and instructs that the operator be allowed to cool down.
Next checks
- Stop repeated cycling
- Record whether the code followed repeated operation or high ambient heat
- Use service if the temperature code recurs or the door has abnormal resistance
35Marantec — M55 numeric display
Electronic defect
LED35
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact M55 table identifies code 35 as an electronic defect and directs the operator to service.
Next checks
- Preserve the code before power removal
- Avoid repeated resets
- Use model-specific electronics service rather than guessing at a replacement part
LED 7 → code 7Marantec — EOS 8-LED display
Programming/reference-point notice
LEDLED 7 → code 7
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
On the verified M4500e/M4700e/M4900e EOS display, LED 7 flashing by itself encodes code 7, a programming/reference-point notice branch.
Next checks
- Confirm the model is M4500e, M4700e or M4900e
- Record what setup step was underway
- Use the exact manual before repeating programming
LED 8 → code 8Marantec — EOS 8-LED display
Adjustment interrupted / reference-switch branch
LEDLED 8 → code 8
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
LED 8 flashing by itself encodes code 8: adjustment interrupted before completion and/or a defective reference-switch branch.
Failure familyTravel, Limit & Position SetupFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Confirm the setup sequence completed
- Preserve the LED pattern
- Use professional service for a persistent reference-switch fault
LED 1+8 → code 9Marantec — EOS 8-LED display
Defective RPM sensor / operator blocked
LEDLED 1+8 → code 9
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The verified EOS table maps LEDs 1+8 to code 9, a defective RPM-sensor or blocked-operator branch.
Failure familyOperator Electronics, Control Board & Thermal ProtectionFailure familyMechanical Resistance & Force Detection
Next checks
- Check for obvious obstruction
- Record whether movement starts
- Escalate RPM-sensor/internal diagnosis
LED 2+8 → code 10Marantec — EOS 8-LED display
Stiff door / force exceeded / force-setting branch
LEDLED 2+8 → code 10
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact table maps LEDs 2+8 to code 10: door movement too stiff, required force exceeded, or working-force setting too low.
Next checks
- Remove obvious obstruction
- Check safe manual door movement
- Do not increase force to mask abnormal door mechanics
LED 3+8 → code 11Marantec — EOS 8-LED display
Maximum run-time limit exceeded
LEDLED 3+8 → code 11
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact table maps LEDs 3+8 to code 11, meaning the operator exceeded its maximum run-time limit.
Next checks
- Record where travel stops
- Check rail/drive movement without internal disassembly
- Stop for a binding or mechanically unsafe door
LED 7+8 → code 15Marantec — EOS 8-LED display
Photo eyes disconnected, misaligned or obstructed
LEDLED 7+8 → code 15
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact table maps LEDs 7+8 to code 15: photo-eye wiring/connection, alignment or beam-obstruction trouble.
Failure familySafety Beam Obstruction, Alignment & InterferenceFailure familySafety Sensor Wiring, Power & Hardware
Next checks
- Clear the photo-eye path
- Realign the sensors
- Inspect accessible low-voltage sensor wiring and connections
LED 1+7+8 → code 16Marantec — EOS 8-LED display
Force-watchdog / sensitivity-sensor fault
LEDLED 1+7+8 → code 16
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact table maps LEDs 1+7+8 to code 16, involving a force-watchdog error or failed sensitivity-monitor sensor.
Next checks
- Stop repeated cycles
- Preserve the LED combination
- Use professional service for force/sensitivity-sensor diagnosis
LED 5+6+7+8 → code 26Marantec — EOS 8-LED display
Undervoltage / operator overloaded
LEDLED 5+6+7+8 → code 26
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact table maps LEDs 5+6+7+8 to code 26, an undervoltage or operator-overload branch.
Next checks
- Stop repeated cycling
- Verify normal outlet power externally
- Use professional service for persistent overload/power diagnosis
LED 2+5+6+7+8 → code 28Marantec — EOS 8-LED display
Stiff/irregular/blocked door or sensitivity branch
LEDLED 2+5+6+7+8 → code 28
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The exact table maps LEDs 2+5+6+7+8 to code 28: stiff or irregular door movement, a blocked door, or operating sensitivity set too low/sensitive.
Next checks
- Remove obvious obstruction
- Check safe manual door movement
- Leave sensitivity adjustment to the exact professional procedure after mechanics are normal
1 flashLinear — LDO33/LDO50 lamp flashes
No problem / remote entered memory
LED1 flash
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The shared LDO33/LDO50 table uses one flash as confirmation that a MegaCode remote control was entered into memory, not as a failure code.
Next checks
- Confirm the remote was just learned
- Test the remote once
- Use another code only if the opener shows a different repeating pattern
2 flashesLinear — LDO33/LDO50 lamp flashes
Shorted wall-station wires
2 flashescount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The LDO33/LDO50 table maps two flashes to shorted wall-station wiring.
Next checks
- Inspect accessible wall-station cable
- Look for staples compressing the low-voltage wire
- Check exposed copper at the terminal screws
3 flashesLinear — LDO33/LDO50 lamp flashes
Safety-beam obstacle
3 flashescount the repeating signal before the pause
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The LDO33/LDO50 table maps three flashes to a safety-beam obstacle.
Next checks
- Clear the beam path
- Check sensor alignment
- Inspect visible low-voltage sensor wiring
4 flashesLinear — LDO33/LDO50 lamp flashes
Force exceeded or motor thermal shutdown
4 flashescount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The shared LDO table lists open/close force exceeded or motor thermal shutdown for four flashes.
Failure familyMechanical Resistance & Force DetectionFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Stop repeated cycles
- Check for obvious door binding or obstruction
- Allow an overheated operator to cool before further diagnosis
5 flashesLinear — LDO33/LDO50 lamp flashes
Vacation switch locked
5 flashescount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The LDO33/LDO50 table maps five flashes to a remote activation while the wall-station vacation switch is locked.
Next checks
- Check vacation/lock switch state
- Unlock the wall station if appropriate
- Retest the remote after lock status is confirmed
6 flashesLinear — LDO33/LDO50 lamp flashes
Motor ran too long / mechanical or electronic failure
6 flashescount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The shared LDO table says the motor ran longer than 30 seconds and identifies a mechanical or electronic failure branch.
Failure familyMechanical Resistance & Force DetectionFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Stop repeated cycles
- Check safe manual door movement only with the door stable
- Escalate if binding or internal diagnosis is required
1 flashLinear — LDCO800 lamp flashes
No problem / remote entered memory
LED1 flash
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
LDCO800 uses one flash as confirmation that a MegaCode remote control was entered into memory, not as a fault.
Next checks
- Confirm a remote was just learned
- Test the remote once
- Preserve any different repeating pattern
2 flashesLinear — LDCO800 lamp flashes
Shorted wall-station wires
2 flashescount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
LDCO800 maps two lamp flashes to shorted wall-station wiring.
Next checks
- Inspect accessible wall-station cable
- Look for compressed/stapled wire
- Check low-voltage terminal connections
3 flashesLinear — LDCO800 lamp flashes
Safety-beam obstacle
3 flashescount the repeating signal before the pause
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
LDCO800 maps three lamp flashes to an obstacle at the safety beam.
Next checks
- Clear beam obstruction
- Check sensor alignment
- Inspect visible sensor wiring
4 flashesLinear — LDCO800 lamp flashes
Open or close force exceeded
4 flashescount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
LDCO800 maps four lamp flashes to exceeded open or close force.
Next checks
- Stop repeated cycles
- Check the door path for obstruction/binding
- Do not increase force to overpower an unsafe door
5 flashesLinear — LDCO800 lamp flashes
Vacation switch locked
5 flashescount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
LDCO800 maps five lamp flashes to remote activation while the vacation switch is locked.
Next checks
- Check wall-station vacation switch
- Unlock if appropriate
- Retest the remote
6 flashesLinear — LDCO800 lamp flashes
Motor ran too long / mechanical or electronic failure
6 flashescount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
LDCO800 says the motor ran longer than 30 seconds and identifies a mechanical or electronic failure.
Failure familyMechanical Resistance & Force DetectionFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Stop repeated operation
- Check for obvious mechanical binding
- Use professional service if the code repeats or internal diagnosis is needed
7 flashesLinear — LDCO800 lamp flashes
Limit error
7 flashescount the repeating signal before the pause
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
LDCO800 labels seven flashes a limit error and lists an encoder-detected error or the down limit being set above the up limit.
Failure familyTravel, Limit & Position SetupFailure familyOperator Electronics, Control Board & Thermal Protection
Next checks
- Record whether limits were recently changed
- Confirm the door itself moves safely
- Use the exact LDCO800 limit procedure only after mechanical safety is established
3 beeps every minuteLinear — LDCO800 optional BBU alarm
Optional BBU battery test low or dead
LED3 beeps every minute
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
The official Linear BBU accessory instructions say the LDCO800 battery unit sounds three beeps every minute when its self-check finds the batteries low or dead and service is required.
Next checks
- Confirm an optional BBU is actually installed
- Verify normal AC power is restored/present
- Use the BBU service/replacement instructions if the repeating alarm persists
1 flash/beepLinear — LDCO850/LDCO852 door-operation flashes/beeps
No problem / remote entered memory
LED1 flash/beep
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
During the LDCO850/LDCO852 door-operation table, one light flash and audible signal confirms a remote control was entered into memory.
Next checks
- Confirm a remote was just learned
- Test the remote once
- Use another code only for a different repeating signal
2 flashes/beepsLinear — LDCO850/LDCO852 door-operation flashes/beeps
Shorted wall-station wires
2 flashes/beepscount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
In the LDCO850/LDCO852 door-operation table, two flashes/beeps point to shorted wall-station wires.
Next checks
- Inspect accessible wall-station cable
- Look for staples or exposed copper
- Check low-voltage terminal connections
3 flashes/beepsLinear — LDCO850/LDCO852 door-operation flashes/beeps
Safety-beam obstacle
3 flashes/beepscount the repeating signal before the pause
Strongest current branchSafety Beam Obstruction, Alignment & Interference
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
In the LDCO850/LDCO852 door-operation table, three flashes/beeps point to a safety-beam obstacle.
Next checks
- Clear the beam path
- Check sensor alignment
- Inspect visible low-voltage sensor wiring
4 flashes/beepsLinear — LDCO850/LDCO852 door-operation flashes/beeps
Open or close force exceeded
4 flashes/beepscount the repeating signal before the pause
Strongest current branchMechanical Resistance & Force Detection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
In the LDCO850/LDCO852 door-operation table, four flashes/beeps indicate exceeded open or close force.
Next checks
- Stop repeated cycles
- Check for obvious obstruction/binding
- Do not raise force to overpower an abnormal door
5 flashes/beepsLinear — LDCO850/LDCO852 door-operation flashes/beeps
Vacation mode
5 flashes/beepscount the repeating signal before the pause
Strongest current branchRemote, Radio & Control-Side Failures
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
In the LDCO850/LDCO852 door-operation table, five flashes/beeps indicate the remote was activated while vacation mode was enabled.
Next checks
- Check wall-station vacation mode
- Disable it if appropriate
- Retest the remote after confirming the mode
6 flashes/beepsLinear — LDCO850/LDCO852 door-operation flashes/beeps
Limit error
6 flashes/beepscount the repeating signal before the pause
Strongest current branchTravel, Limit & Position Setup
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
For LDCO850/LDCO852, six door-operation flashes/beeps indicate a limit error because the down and up limits are set too close together.
Next checks
- Record whether limits were recently changed
- Check safe door movement
- Use only the exact LDCO850/LDCO852 limit procedure after mechanical safety is established
7 flashes/beepsLinear — LDCO850/LDCO852 door-operation flashes/beeps
Encoder error
7 flashes/beepscount the repeating signal before the pause
Strongest current branchOperator Electronics, Control Board & Thermal Protection
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
For LDCO850/LDCO852, seven door-operation flashes/beeps mean the encoder detected an error.
Next checks
- Stop repeated cycles
- Check for obvious binding or obstruction
- Use professional diagnosis if the encoder code repeats
2 beepsLinear — LDCO850/LDCO852 battery alarm beeps
Low battery
LED2 beeps
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
In the separate LDCO850/LDCO852 battery alarm table, two audible beeps mean the backup battery is low.
Next checks
- Confirm normal AC power is present
- Allow the manual's charging interval before condemning the battery
- Keep the door path clear because battery backup can move the door
4 beepsLinear — LDCO850/LDCO852 battery alarm beeps
Battery has no capacity
LED4 beeps
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
In the separate LDCO850/LDCO852 battery alarm table, four audible beeps mean the battery has no capacity.
Next checks
- Confirm this is the battery-only alarm context
- Verify the installed battery and AC power state
- Follow the exact battery replacement/service path
5 beepsLinear — LDCO850/LDCO852 battery alarm beeps
Battery shorted
LED5 beeps
Strongest current branchManufacturer-specific signal
Evidence strengthExact manufacturer code / LED state
Do not assumeDo not translate this code across brands or generations
In the separate LDCO850/LDCO852 battery alarm table, five audible beeps mean the battery is shorted.
Next checks
- Stop repeated operation
- Keep the door path clear
- Use the model-specific battery/service procedure rather than treating this as the door-operation five-count code
Conservative by design: the database expands only after source verification. A missing code is preferable to a plausible but unsupported interpretation.