What happened right before the failure?
A door that will not open can be caused by the counterbalance system, opener, power, lock, track hardware, or an obstruction. The symptom that came first often narrows the problem.
| Symptom | Likely direction |
|---|---|
| Loud bang, then door became very heavy | Spring failure |
| Opener has no lights or response | Power or control issue |
| Motor runs but door does not travel | Opener drive/trolley or mechanical issue |
| Door rises unevenly or jams | Cable, roller, or track issue |
Do not repeatedly press the opener button if the door is crooked, extremely heavy, or you suspect a broken spring.