You won't have to flex your muscles just to roll the window glass up or use the crank handle to pull it all the way down. With power windows, all it takes is a flick of a switch. The window regulator, which moves the pane of glass up and down, is powered by the window motor. When a power window gets stuck or stops working, a busted motor is often the one to blame. However, this may also be due to faulty switches, a broken window regulator, a damaged wire, or lack of power or electricity. To know if a bad motor is the real cause of the problem, you'll have to check a few things.
Figuring out if you have a bad window motor
- Check the fuse. Use the owner's manual when looking for the fuse box and other electrical components connected to the window motor. Inspect the fuse to see if it's blown. In case it's damaged, it should be replaced with a new fuse of the same amperage.
- Have the relay tested. As you remove the power window relay, install a jumper (terminal 30 and 87) to see whether the motor is working or not. If the power windows work while using a jumper, then there's nothing wrong with the motor.
- Test the switch using a voltmeter or ohmmeter. The reading should be around 12VDC for terminal 4 and terminal 5. Terminals 1-4 and 2-3 should have a reading of less than 1 ohm if the switch is open. If the switch is close, you should be able to observe low resistance from terminals 1-3 and 2-5. Low voltage is an indication of a motor or switch problem.
Replacing a broken window motor
Step 1: Disengage the door access panel, located somewhere around the handle, to remove the entire door panel. This is necessary if the access panel covers the bolt that supports and holds the door panel. A door panel removal tool should be used to loosen the access panel until this can be slid off.
Step 2: Detach the control switch panel, the one covering the window control. (Note: If the vehicle is designed with a control switch that's integrated into the door panel, you can just skip this step and proceed to step 4). Use a door panel removal tool to easily raise and slip off the switch panel.
Step 3: Disconnect the electrical wiring by pulling out the connector.
Step 4: Pull out the entire door panel after removing its bolts and screws.
Step 5: Take out the plastic insulator, the one protecting the window motor, wiring, and regulator. You'll easily find this insulator once the door panel has been removed.
Step 6: Use a center punch and hammer for removing the regulator. The punch should be hammered into the rivets' center pins. (Note: Not all regulators are held by rivets. In such a case, you will have to remove the bolts instead.) Slide out the regulator that's connected to the motor from the chassis of the metal door. This should come out through the chassis' gap. (Note: Tape the closed window to keep it safe as you remove the regulator and motor.)
Step 7: Detach the regulator from the window motor. To do this, the regulator arm should be clamped to a bench vise. Drill a hole that measures 0.25 inch through the center of the plate, the one that holds the chassis. To be safe, plug the hole with a nut and bolt. This will keep the coil spring from breaking the regulator arm and gear that it counterbalances. The rivets or any fastener that holds the motor should be removed. When drilling off the rivets, be sure to use a drill bit that matches the rivets' diameter. Finally, slip off the motor and disconnect it from the regulator.
Step 8: Apply some grease on the gear before putting in the new window motor. The motor should easily line up with the mounting holes and should be flush to the regulator. The motor can be attached and sealed with rivets or, in other cases, nuts and bolts or screws. The nut and bolt used in the hole on the plate (in step 7) should be removed. After this, the regulator arm should be unclamped.
Step 9: Put back the regulator with its new window motor. The unit can easily slip in through the door chassis' opening or gap. The regulator's holes should line up with those of the door chassis. Secure the regulator with the rivets you've removed earlier or with any fastener (such as bolts and nuts) that holds it in place. After the door panel was reinstalled to the door chassis, the wiring connector should be fixed back into the control switch. Reattach and secure all the panels that were removed.