Garage door safety sensor (photo eye) with its indicator light on

Generic photo: Jud McCranie · CC BY-SA 4.0

Garage door opener safety tests: monthly reversal test, photo-eye test and after-adjustment retest

Chamberlain/LiftMaster say the safety reversal system must be tested every month and after any adjustment to force, travel, the door arm, springs, hardware or the floor. Place a 1-1/2 in object (a 2x4 laid flat) centered under the open door and close it: the door must reverse on contact. Then break the photo-eye beam while closing: the door must stop and reverse. If it fails, adjust per the manual or take the opener out of service until a door tech fixes it.

Cross-checked ~20 min easyBrands: Chamberlain, LiftMaster, Craftsman, Genie, Linear, All

Before you start

Keep people, pets and vehicles out of the door path during tests
Do not adjust springs, cables or bottom brackets; they are under high tension and are a door-tech job
Never bypass, remove or relocate the photo eyes higher to stop a nuisance reversal

Diagnostic steps

Unlock all 6 steps with expected values

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