A humming opener has power, but that does not prove the motor is the only problem. The door may be too heavy, mechanically locked, disconnected, bound in the track or affected by a failed drive component.
Stop repeated attempts
A motor that hums while the door remains still may be stalled against resistance. Repeated attempts can overheat the opener or damage gears, belts, chains, trolleys and the door connection.
Check the door before blaming the motor
A broken spring can leave the opener trying to lift the full door weight. A manual slide lock, seized roller, bent track or loose cable can also prevent movement.
Look for a spring gap, crooked bottom section or loose cable without touching any loaded hardware.
Listen for the difference between hum, click and movement
A brief click with no motor sound follows a different diagnostic path from a motor that runs while the trolley stays still. Note whether the opener light activates, the rail moves and the door begins to lift at all.
A complete repair separates two systems
The door should be evaluated for safe balance and travel before the opener is diagnosed under load. Only then can the motor, capacitor, drive, trolley, limits and controls be assessed accurately.