Garage Door Opener Troubleshooting: 9 Common Faults
Opener humming, door reversing, remote dead? Work through nine common garage door opener faults, what each symptom actually means, and which are worth repairing.
Before blaming the opener, disconnect it. Pull the red release cord and lift the door by hand. If the door is heavy, binding or crooked, the fault is the door and no amount of opener work will fix it. If it glides up easily and stays put, read on.
1. Motor hums, door doesn't move
A stripped nylon drive gear, nine times out of ten. Cheap part, worth repairing on anything under about twelve years old.
2. Door closes then reverses immediately
The photo-eye sensors. Check both indicator lights are steady, the lenses are clean, and nothing is parked in the beam. A blinking light means misalignment or a damaged wire.
3. Door reverses partway down
Either the close-force setting is too low for a door that's gained friction, or something is genuinely binding. Investigate the binding first — turning the force up to overpower a problem is how doors get damaged.
4. Remote works, wall button doesn't (or vice versa)
If only one control fails, the opener itself is fine. A dead wall button usually means a broken low-voltage wire or a failed button. A dead remote is usually the battery, then the programming, then the logic board's receiver.
5. Remote only works up close
Weak battery, a damaged antenna wire hanging from the opener head, or radio interference — LED bulbs in the opener are a surprisingly common culprit.
6. Opener runs by itself
A shorted wall-button wire, a stuck button, or a neighbour's old fixed-code remote. Any opener made before the mid-90s without rolling codes should be replaced outright on security grounds.
7. Door won't close and the light blinks
Most openers use a blink count to report a fault code. Count the flashes and check the manual — it's usually the sensors, but the code narrows it fast.
8. Grinding from the head unit
Drive gear or sprocket. Stop running it before the sprocket goes too.
9. Nothing at all
Check the obvious first: the opener is unplugged, the GFCI outlet has tripped, or the breaker is off. After that, a failed capacitor or logic board.
Repair or replace?
Under ten years with a common fault, repair it. Over fifteen, noisy, no rolling-code security, no battery backup — a new belt-drive unit is quieter, safer and will keep working through a power cut.