Operator Error Codes

Commercial — LiftMaster Logic 5.0 Error Codes

H/J/GH/RGJ operators, LOGIC 5.0 board

Count the number of times the diagnostic light blinks after a failed operation, then match the pattern below. Tap share on any code to send it to another tech.

1 flash

Open limit fault

Reprogram open limit or check limit switch.

2 flashes

Close limit fault

Reprogram close limit or check limit switch.

3 flashes

No movement detected after start

Check motor connections, gear engagement, and that the door is not physically locked.

4 flashes

Entrapment circuit fault (photo eyes or edge sensor)

Check all safety devices: photo eyes, sensing edges, and their wiring.

5 flashes

Motor thermal overload

Let motor cool. Check for excessive door weight or mechanical resistance.

6 flashes

Input power phase loss (3-phase)

Check all three phases at the disconnect. A blown fuse or tripped breaker on one phase causes this.

7 flashes

Max run timer exceeded

Door did not reach the limit in the allowed time. Check for obstructions or low force settings.

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