Why does my garage door opener only work sometimes?

Start with the two cheapest suspects: the remote and the safety sensors. A remote with a weak battery works from the driveway one day and not the next, and a safety sensor that is slightly out of line lets the door open but not close. The wall button, the opener and the door itself come after those.

Sort out which symptom you have

Work out what "sometimes" means, because it points to different parts.

• The wall button always works, the remote does not. The problem is in the remote or its link to the opener, not the motor.
• Neither works, but the door moves when you pull the cord and lift it by hand. Suspect the opener's power or its logic.
• The door opens but will not close, or starts down and goes back up. That is the safety system, covered below.
• The opener hums or clicks and the door does not move. Stop and read the last section: this can be the door, not the opener.

Remote works only close by

A remote that needs you to be nearly at the door is almost always a tired battery. The remote's battery is the first thing to change. Chamberlain's 3-button visor remote, for example, uses a 3V coin-cell lithium CR2032 battery.^[1] Check the type printed on your remote, since models differ.

If a fresh battery does not help, reprogram the remote. The Learn button sits under the opener's light cover: look under the garage door opener light cover, on the same side as the antenna.^[2] The full procedure is in how to program a garage door remote. A remote that works in one spot of the driveway and not another points to interference or a hidden antenna, so also check that the antenna wire hanging from the motor unit has not been bent, taped up or tucked behind a shelf.

Door will not close, or reverses

If the door goes up but will not come down, the safety sensors are the usual cause. Chamberlain says to check that your safety sensors are aligned, as this is a common cause for garage doors not closing.^[3] The sensors are a pair of small eyes on either side of the door near the floor. CPSC says that an electric eye, if used, should be installed at a height of 4 to 6 inches above the floor.^[4]

Look for a bumped bracket, a sensor pointing at the ground, dirt or a spider web across a lens, or a box or tool in the beam path. Wipe both lenses with a dry cloth, nudge each sensor until it faces the other, and watch the indicator lights if your model has them. Your owner's manual explains what each light means.

If the door actually hits something while closing, that is the system doing its job: the door will reverse, the opener will beep and the lights will flash 5 times.^[3] Check the floor line for anything in the way before you assume a fault.

Check the door before you blame the opener

An opener that works unevenly is sometimes fighting a door that binds or is out of balance. LiftMaster's monthly checklist starts with this: manually operate door, and if it is unbalanced or binding, call a trained door systems technician.^[5] CPSC adds that if doors are not "balanced," or if they bind or stick, they should be serviced by a professional.^[4]

To check balance, close the door, pull the red release cord to detach it from the opener, and lift the door by hand to about waist height. A balanced door stays put. One that drops or shoots up has a spring problem, and springs are not a do-it-yourself job: see how garage door springs work.

Stop and call a pro if

• The door is heavy, uneven or drops when released. That points to springs or cables under tension. Keep clear of them.
• The opener runs but the door does not move, or the door moves a few inches and stops. Worn gears, a sheared trolley or a door problem needs diagnosis.
• The door does not reverse when it strikes a 2x4. CPSC says that in that case the opener should be disengaged until it is adjusted, repaired or replaced.^[4]
• Nothing you changed makes a difference after a new battery, reprogramming and aligned sensors. Wiring or the logic board may be failing.

When the opener is old, read should I replace my garage door opener or repair it and what a new opener costs installed in Virginia. Keeping it healthy afterwards is covered in how to maintain a garage door opener.

Getting help in Virginia

Browse more garage door answers or see garage door services near you. When you are ready, describe the problem once and local garage door businesses quote it.