Garage Door Hits a Certain Spot and Will Not Close

Safety Systems

• If a garage door closes with full force on a vehicle, the door can cause expensive damage to the body of a car. If the accident happens to a person or pet, serious injury or death can follow. To prevent these mishaps, garage door opener manufacturers build fail-safe systems that determine whether the door closes or backs off. Sensors measure actual resistance against the force the motor should encounter at different door positions. Excess resistance causes the door to stop and reverse. Garage door openers can include infrared systems that test the opening and stop the door if something interrupts the beam.

Adjustments

• To match the garage door opener to new installations and different door heights, the systems allow manual setting of the upper and lower limits of movement. A newly installed door might move down only a few feet before stopping, even without encountering an obstacle. New doors might not completely open, either. Setting a new door to open and close properly requires 10 different steps under the system developed by Genie. Other manufacturers provide different adjustment procedures, but each opener needs careful adjustment before first use. As installations age, owners might need to reprogram these settings, according to Genie website.

Aging

• Resistance in the door track can change because of accidents that push the track out of line or from faulty installation. Checking tracks with a carpenter's level should point out any major misalignment. Dirt and rust in aging roller bearings can cause doors to jam and reverse. Lubricating the rollers, bearings and door hinges and cleaning the track can correct minor problems. Debris sometimes lodges in the overhead tracks, so inspect and clean all parts. Check infrared sensor systems as well. Faulty sensors or sensor misalignment causes the door to reverse without closing, according to Chamberlain Do-It-Yourself Products.

Controls

• If you find no mechanical problems, check the controls. Controls on the garage door's motor housing set the machine's run time. Changing how long the motor runs determines how far the door actually travels in either direction. Openers might adjust with just two control knobs or with a complicated system of timers, mode buttons and both "Up" and "Down" buttons. Curious children might reset controls, and small changes introduce large errors in the door's operation. Restoring settings to normal requires an operation manual and a start at step one. On some systems, changing one limit affects both settings, so follow procedures exactly.