LiftMaster / Chamberlain Error Codes

Safety sensors (photo eyes) open or disconnected

Check photo eye alignment and wiring. Both LEDs should be solid.

Safety sensors shorted or wiring fault

Inspect wiring between operator and photo eyes. Look for pinched, cut, or shorted wires.

Door control wired to wrong terminal

Verify the wall button is connected to the correct terminals on the operator (not the safety sensor terminals).

Safety sensor eyes slightly misaligned

Photo eyes are communicating but marginal. Clean lenses and realign for solid LEDs.

Motor thermal overload or RPM sensor fault

Let the operator cool for 15 minutes. If it continues, check for mechanical resistance in the door.

Motor running too long / travel limit issue

Adjust travel limits. The operator may be running past its endpoints.

Operator needs reprogramming

Re-learn travel limits: hold the LEARN button, then program open/close limits per the manual.

MyQ / Wi-Fi communication error

Check Wi-Fi connection. Power cycle the operator and router.