Garage door motor not working: how to diagnose it

If your garage door motor is not working, the fault is usually one of 4 things: no power reaching the unit, a stripped drive gear (the motor hums but nothing moves), a blown capacitor, or a mechanical fault like a broken spring that has overloaded the motor. The quickest diagnosis is to listen: total silence points to power or the logic board, while humming with no movement points to a stripped gear or seized door. A motor repair or replacement in Adelaide costs $350 to $750, and diagnosis is best left to a vetted specialist once the simple checks are done.

Diagnose by what the motor does

Listen carefully when you press the button. The behaviour narrows the fault fast.

What happens	Likely cause	Indicative cost
Nothing at all, no light, no sound	No power, tripped switch, or dead board	$150 to $400
Motor hums, door does not move	Stripped drive gear or seized door	$350 to $750
Motor runs, door moves slowly then stops	Failing capacitor or worn motor	$350 to $750
Motor runs fully but door stays put	Disconnected release cord	Free to reconnect
Motor strains, then reverses	Broken spring overloading the motor	$180 to $350 (spring)

That last row matters. A motor that strains and gives up is often a symptom, not the fault. The real problem is frequently a snapped spring forcing the motor to lift the full door weight. Confirm with the broken garage door spring guide before you replace an opener that is actually fine.

Run the simple checks first

Before quoting a motor, a good specialist rules out the free fixes, and so should you.

1. Power: is the point switched on and the safety switch un-tripped? Plug something else in to confirm.
2. Release cord: has it been pulled, disconnecting the motor from the door? Re-engage it and test.
3. Wall button: if the remote does nothing but the wall button works, the opener not working checklist covers the remote and receiver side.
4. Manual lift: pull the release and lift by hand. If the door is very heavy, the fault is a spring, not the motor.

If those pass and the motor still will not drive the door, you are into a genuine motor repair. See the full cost bands to budget, or use the motor replacement cost estimator for a tailored figure.

Repair or replace the motor?

A stripped nylon drive gear is a cheap, common repair that brings an otherwise-good opener back to life. A burnt-out motor, a failed logic board on an older unit, or a discontinued opener usually makes replacement the smarter spend, because a new drive gives you a warranty and quieter, safer operation. In Adelaide's salt-air belt (Port Adelaide, Henley, Glenelg, Hallett Cove), motor circuit boards corrode early, so coastal openers reach replacement sooner than inland ones.

Frequently asked questions

Why does my garage door motor hum but not open?

Humming with no movement almost always means a stripped drive gear or a door that is physically stuck (a broken spring, seized rollers, or an off-track door). The motor is trying but cannot move the load. A specialist will check the door is free before touching the motor.

Can a broken spring damage the motor?

Yes. Without the spring's counterbalance, the motor lifts the entire door weight, which strains and eventually burns out the drive gear or motor. This is why running a door with a failed spring is a false economy.

Is it worth repairing an old garage motor?

If the unit is a well-known brand and the fault is a drive gear or capacitor, repair is usually worthwhile. If it is 15-plus years old, the board has failed, or parts are discontinued, replacement often costs less over its life and adds a warranty.

To pin down the fault fast, get matched with vetted Adelaide specialists free and compare quotes.