Garage door opener hums but door does not move; chain or belt does not travel.

Safety first: Disconnect mains power. Secure the door in the open position with clamps if you need to work under it.

• Confirm symptom: Activate the opener briefly and listen. A humming motor with no chain/belt movement strongly suggests internal drive failure.
• Check external hardware: Ensure the chain/belt is still on the sprocket and the carriage is engaged. If the sprocket turns but the rail does not move, the issue is in the carriage or rail, not the gear.
• Open housing: Remove the Garador operator cover and inspect the main drive gear and coupling. Look for plastic shavings, missing teeth, or a split coupling.
• Replace gear kit: If the gear is stripped, install a genuine Garador drive gear kit or, if not available separately, replace the complete motor/gearbox assembly.
• Check door balance: Before returning to service, correct any door balance issues that may have overloaded the gear.