How to Troubleshoot a Kenmore Garage Door

Replace the battery in the remote if the door is not opening or closing properly with the remote. A weak battery may not have enough power to signal the motor to start. Clear the sensors and check for any loose wiring or objects that can block the signal. Check to make sure the opener itself is properly plugged and and has not become disconnected.

Check the door rails for obstructions if the door only opens or closes part way. A shifting foundation may gradually move the door out of alignment. This will eventually trigger a safety shutdown of the motor when the rollers catch and hold up on misaligned rails.

Open the case cover and watch the gears if the motor is running but the door does not move at all. With extensive use, the internal gears may wear out and no longer engage the drive chain. If the gears are turning on an older Sears model but the drive does not move, that is likely the problem.

Examine the belt or chain drive where it connects to the motor. All models have the ability to disconnect the drive so that the door can be opened manually in case of a power failure. If the drive connection slips off the motor by accident, or is bumped off while moving something in the garage, the door will no longer work as expected.

Watch the springs as the door opens and closes. A loose or unbalanced spring will cause the door to sag on one side and not operate properly.