Power windows are an often-overlooked luxury in late-model vehicles, until they stop working. Toll booths, drive-through restaurants,and drive-up ATM machines all require the regular use of at least the driver-side window. A malfunctioning power window is typically caused by one of three problems or failures: a failed switch or power connection, a broken actuator, or a mechanical blockage or misalignment of the track. Basic investigation and testing can help you determine the problem with your power window, and some repairs can be done at home with common tools.
Note the general nature of the problem. Check whether all the windows are malfunctioning or just one. Listen for the sound of the window motor when the switch is depressed, and for any other mechanical noise that could be caused by misalignment or blockage. If the window and motor are completely silent when you press the switch, the problem is likely caused by a bad electrical connection or failed motor.
Consult your owner's manual for the location of the power window fuse. Replace the fuse with a new one of equal rating and check if the window functions properly again.
Purchase a 12-volt test light at an automotive parts store. These testing lights consist of two electrical probes, and a small light that illuminates if a 12-volt current is present when connected to a circuit. Turn the ignition key to the "Acc" position so that the electrical power is on, but the engine is off. Follow the path of the wires connecting the fuse to the window switch and touch the probes on either side of each connection and switch to determine if the power is being interrupted.
Remove the door panel of the afflicted window. Use a flat-head screwdriver to pry open all the plastic clips that hold the door panel to the door frame. You may also need to remove some metal screws using a Phillips-head screwdriver. When all the fasteners are removed, carefully lift the door panel upward and away from the door frame to remove it.
Use the test light to check all connections leading to the window motor. If there is uninterrupted power at all connections, replace the window motor with a factory replacement part, available through your dealership, and most automotive parts retailers. If you discover loss of power elsewhere, disconnect the battery and clean any terminals using some spray-on circuit cleaner. Faulty switches can be replaced with genuine parts ordered from you local dealership or auto parts store.
Inspect the window track for any blockage. If the window anchors have come off their track, you may be able to place them back in by hand. If not, take the vehicle to a repair technician.
