Symptom: The Door Goes Up, But it Only Goes Down When You Hold Down the Wall Switch
Fix: Align or replace the safety sensor
If the door goes up but goes down only when you hold down the wall switch, check to see that the safety sensors are in alignment. The small light on each sensor should be lit up when nothing is between them. Door sensors do go bad, so if no light is showing at all, you may need to replace them. You can save yourself some time by using the existing wires. Also, direct sunlight shining on sensor eyes can make them misbehave.
Symptom: You Have Power to the Outlet, But There's No Sound or No Lights When You Push the Wall Switch and Remotes
Fix: Replace the circuit board
If the outlet has power, but there's no sound or no lights when you push the wall switch and remotes, you probably have a bad circuit board. Lightning strikes are the most frequent reason for the demise of a circuit board. The circuit board consists of the entire plastic housing that holds the lightbulb and wire terminals. The part number should be on the board itself.
Replacing a circuit board sounds scary, but it's really quite easy. It will take 10 minutes tops and only requires a 1/4-in. nut driver. Just follow these steps: Remove the light cover, take out the lightbulb, disconnect the switch and safety sensor wires, remove a few screws, unplug the board and you're done. A circuit board will cost about $80, so make sure you protect your new one with a surge protector. You can buy an individual outlet surge protector at a home center for less than $10.
Symptom: Everything Works Fine Except the Lights
Fix: Replace the light socket
If the bulbs are OK but don't light up, you probably have a bad light socket. To replace the socket, you'll need to remove the circuit board to get at it. Use the same steps as in 'Replace the Circuit Board' (above) to accomplish this.
Once the circuit board is removed, pop out the old socket by depressing the clip that holds it in place. Remove the two wire connections and install the new socket. Replacement sockets cost less than $15.
Be sure to use a bulb of the correct wattage. Using lightbulbs with a higher wattage than the socket is rated for will cause a socket to fail. Not only is this bad for the socket, but it can also be a fire hazard. If your light cover has turned yellow from heat, you're probably using too strong a bulb.