Automatic garage door openers provide great convenience, keeping your garage locked and secure when you're away, and opening the door with the touch of a button when you get home. They can be finicky, though, and among the possible malfunctions, the door might behave erratically, the motor may make noises or the remote might stop working. Many problems are easily fixed, and you'll need your owner's manual handy to help navigate your specific model. It's usually available on the manufacturer's website.

Erratic Door Operation

When you press the button on the wall switch or on the remote, the door is supposed to open and close smoothly, but it may fail to close, fail to open, or close partway and then open again. A few simple adjustments usually clear up these problems.

Door Won't Open

  • If you can hear the motor operating normally, but the door doesn't move, it may be because someone pulled the emergency disconnect. Reconnect the door to the trolley by lifting the door manually until the door arm clicks into place in the trolley.
  • The motor may run for a few seconds and stop without budging the door. Check the tracks for kinks or obstructions that could be preventing the door from moving. Look also at the torsion spring, located just above the door. If the spring is broken or you see bends in the tracks, call a repair professional. Attempting to repair these things yourself is dangerous.
  • If the door opener hums continuously when you press the button or remote, but the door doesn't open, the fault is often a worn capacitor. Check the location of this part in the motor housing, using your manual. Unplug the door opener, disconnect the capacitor, unscrew it from the housing and replace it.

Door Won't Close

  • The door may fail to move, even though the motor is running normally. That's usually because someone pulled the emergency rope and the trolley is disconnected from the door arm.
  • If the door closes partway, then opens again, it's often because the safety sensors, located on either side of the doorway, detected an obstruction or are out of alignment. A light on the opener usually flashes when the sensors stop the door from closing. Clear cobwebs from the sensor lenses and realign them, if necessary, following the instructions in your manual.
  • When the door closes all the way, then opens again, it's usually because the close limit range isn't set far enough. You can adjust this by turning a limit screw on the opener housing. Consult your manual for location of the screw and specific instructions.

Switch Malfunctions

Garage door openers have a wall switch and a remote that usually stays in the car. Sometimes one works while the other doesn't and vice versa, and sometimes neither switch works.

The Remote Doesn't Work

The most common cause of a remote malfunction is that the batteries are weak and need to be replaced. If the batteries are good, the remote itself may be damaged -- you can usually find a replacement at a building supply outlet or online. The new remote might have to be programmed to work with your receiver -- consult your owner's manual for details.

The Wall Switch Doesn't Work

Most wall switches have a light to indicate that they are receiving power. If the light is off, check the breaker that controls the circuit -- it may have tripped. If the switch has power, then the problem may be a loose connection. Turn off the breaker, and tighten the wire connections in the switch and the motor housing.

Nothing Works Even Though There's Power at the Outlet

A loose or burned-out electronic component in the opener's circuit board can prevent your opener from receiving power. To investigate, unplug the opener, open the housing and remove the circuit board -- which is usually a matter of unscrewing a few screws. Melted or burnt components indicate the need to replace the circuit board.

There's a Loud Grinding Sound when the Motor Is Running

When you open the housing, inspect the gears for damage. You'll probably find that some teeth have sheared off or worn down, and that the motor is turning freely. You can replace the gears yourself with the help of your manual, but you may prefer to get a pro to help with this one or simply replace the opener.