Garage Door Opener Repair Guide
When working on your garage door opener ensure that you unplug it from the mains outlet, or switch off the circuit breaker. If you do not feel confident in your abilities contact a professional for help.
Always consult the garage opener manual, see garage opener manuals.
If your garage opener does not respond when you press your remote control, try another remote, if it responds the problem is with the first remote control, if it does not respond, press the wall mounted hard wired push button, if it responds the problem is either with both remote controls which is unlikely, or more likely you have a faulty receiver or a problem with severe interference from other radio signals (see article about automatic door closers). An indication that there is interference is when you activate your remote control right next the garage door opener and it activates, and as you move further away it fails to activate.

- Wall mounted push button
If neither the remote controls or wall mounted push button operate the opener ensure that its power cord is plugged into a working power outlet. If it is plugged in, test that there is power coming from the outlet, to do this plug in a known working appliance such as a hairdryer for example and switch it on, if it works you have power, if it does not the power outlet is the problem.
If you have power going to the opener and you can smell a burnt electrical odor, it is likely that the motor start capacitor is at fault, without special test equipment the only way to confirm this is to replace it.
If your garage door will not close from the open position and reverses immediately or part way down there is a safety beam problem, usually there is a safety light on the opener which will flash when the safety beam is activated or faulty. Clean the photo beams with a clean damp cloth, check if the door now operates, if it does not, check that the safety beams have not become misaligned, there is normally a light on one of the sensors that indicates when they are correctly aligned, if the light is on it means they are not aligned, the light off indicates they are aligned. If they are not aligned try adjusting them, if this does not work they are probably faulty.

Motor force adjustment
If the safety beams are ok and the door still reverses whilst closing, locate the close force adjustment, sometimes located under the light lens cover or on the back of the opener, now increase the close force adjuster in small increments and operate the door at each increase until the door closes, if you need to increase the force to maximum, it indicates a problem with the springs,bent track, worn or damaged rollers and hinges. Always consult the garage opener manual (see garage opener manuals).
The force sensor can be overridden by pressing and keeping pressed the wall mounted push button, do this, and if you can hear the motor operating but the door is not moving it is likely that one of the nylon drive gears has worn and needs replacing. The problem could also be that the travel carriage teeth that engage with the screw drive have become worn, in this case you need to replace the trolley assembly.

Worn drive gear
You can find a list of parts available on the garage door opener parts page.