Work through these in order
A door that will not open has a short list of causes, and a technician rules them out in a specific sequence because each one is cheaper and more likely than the last. You can do the first five yourself in about ten minutes. If none of them is it, the sixth through eighth are ours.
1. The obvious one: power
Check the opener is plugged in and the outlet is live — plug a lamp into it. Check the breaker. Ceiling outlets in garages are frequently on a GFCI that has tripped, and the reset button may be on a different outlet elsewhere in the garage or even outdoors. If the opener's light comes on but the motor does nothing, power is fine and you can move on.
2. The remote and keypad
If the wall button works but the remote does not, it is the remote: battery first, then reprogramming. If neither works but the opener has power, the receiver or logic board is a candidate. If the keypad works intermittently in cold weather, that is usually a dying battery in the keypad rather than the opener.
3. The lock
Most openers have a vacation or lock mode, engaged by holding the lock button on the wall control. It disables all remotes deliberately. People trigger it by accident constantly, particularly children and cleaners. A blinking LED on the wall control usually indicates it. Hold the lock button for a few seconds to clear it.
4. The manual release
If the opener runs, the chain or belt moves, and the door stays still, the carriage has been disconnected from the trolley — someone pulled the red cord. Reconnect by pulling the cord toward the door (or per your model's instructions) and running the opener until the carriage clicks back on.
5. A broken spring
Look at the torsion spring on the shaft above the door. A two- to three-inch gap in the coil means it has snapped. On extension springs, look for one hanging slack alongside the track. If a spring is broken, stop here. The door is now unsupported deadweight and running the opener will damage it. This is a call, not a fix.
6. Cable off the drum
If one side of the door sits lower than the other, or you can see slack cable hanging, a cable has come off its drum or snapped. The door is out of square and forcing it will bend track and damage panels. Leave it.
7. The opener gear
A chain-drive opener that hums or grinds without moving the chain has usually stripped its plastic drive gear. It is a common and inexpensive failure — a gear kit is $129 to $220 fitted — and it does not mean the opener is finished.
8. Logic board or capacitor
No response at all with confirmed power, or a single click and nothing, points at the capacitor or the logic board. Boards run $180 to $340 fitted depending on brand. On units older than about twenty years we will tell you honestly whether the board is worth it against a replacement opener.
What to do right now if the car is trapped
Pull the red release cord to disconnect the opener, then try lifting the door by hand. If a spring is intact the door should be light enough for one person to raise. If it feels like lifting a piano, the spring has gone — do not force it, because doors do come back down. Call and we will get someone out; a trapped vehicle counts as an emergency and we dispatch on it around the clock.
