Power window system — description and check
Note: These models are equipped with a Body Control Module (BCM) incorporated with the window system. Several systems are linked to a centralized control module that allows simple and accurate troubleshooting, but only with a professional-grade scan tool. The Body Control Module governs the door locks, the power windows, the ignition lock and security system, the interior lights, the Daytime Running Lights system, the horn, the windshield wipers, the heating/ air conditioning system and the power mirrors. In the event of malfunction with this system, have the vehicle diagnosed by a dealership service department or other qualified automotive repair facility.
1. The power window system operates electric motors, mounted in the doors, which lower and raise the windows. The system consists of the control switches, the motors, regulators, glass mechanisms, the Body Control Module (BCM) and associated wiring.
2. The power windows can be lowered and raised from the master control switch by the driver or by remote switches located at the individual windows. Each window has a sea rate motor that is reversible. The position of the control switch determines the polarity and therefore the direction of operation.
3. The window motor circuits are protected by a fuse. Each motor is also equipped with an internal circuit breaker; this prevents one stuck window from disabling the whole system.
4. The power window system will only operate when the ignition switch has activated the Retained Accessory Power (RAP) relay. In addition, many models have a window lockout switch at the master control switch which, when activated, disables the switches at the rear windows and, sometimes, the switch at the passenger’s window also. Always check these items before troubleshooting a window problem related to any of the other windows besides the driver’s window. Window lock-out does not affect the driver’s window.
5. These procedures are general in nature, so if you can’t find the problem using them, take the vehicle to a dealer service department or to an independent repair facility that specializes in electrical repairs.
6. If the power windows won’t operate, always check the fuse and circuit breaker first.
7. If only the rear windows are inoperative, or if the windows only operate from the master control switch, check the rear window lockout switch for continuity in the unlocked position. Replace it if it doesn’t have continuity.
8. Check the wiring between the switches and fuse panel for continuity. Repair the wiring, if necessary.
9. If only one window is inoperative from the master control switch, try the other control switch at each individual window.
Note: This doesn’t apply to the driver’s door window.
10. If the same window works from one switch, but not the other, check the switch and/or wiring for continuity.
11. If the switch tests OK, check for a short or open in the circuit between the affected switch and the window motor.
12. If one window is inoperative from both switches, remove the switch panel from the affected door. Check for voltage at the motor (refer to Body for door panel removal) while the switch is operated.
Note: There are voltage and ground signals present at the switch connector. However, on 2010 and later models, there are also two data lines to the BCM that are not true positive/negative signals. Be sure you are testing the correct leads. Do not apply voltage or ground to any leads you are not sure of. Seek professional help in diagnosing any problems with the window circuits if you are unsure.
13. If voltage is reaching the motor, disconnect the glass from the regulator. Move the window up and down by hand while checking for binding and damage. Also check for binding and damage to the regulator. If the regulator is not damaged and the window moves up and down smoothly, replace the motor. If there’s binding or damage, lubricate, repair or replace parts, as necessary.
14. If voltage isn’t reaching the motor, check the wiring in the circuit for continuity between the switches and the BCM, and between the BCM (if applicable) and the motors. You’ll need to consult the wiring diagram. If the circuit is equipped with a relay, check that the relay is grounded properly and receiving voltage.
15. Test the windows to confirm proper repairs. To verify if the motor is getting the needed voltage or ground, a simple but effective test is to sit in the car with the ignition on, open a door and look at the dome light. Then operate the switch to the faulty window. If you see the dome light dimming slightly this is a good indication that the motor is getting power and is probably a stuck motor or faulty wiring. Do not hold the switch on for very long when a motor is stuck or wiring is in question or more damage may occur. Finally, in some cases, a good rap on the door panel in the general area of the window motor — while the key is on and the window switch is depressed in the direction the window needs to move — will free up a stuck motor temporarily. You can damage the door panel or more internal components if you hit it too hard or are too aggressive.
Window express down programming
Note: Any time the battery or window motor are disconnected, you will need to perform this procedure to reestablish the auto feature.
16. Lower the window to its lowest position, holding the switch in the Down position for an additional five seconds.
17. Raise the window to its highest position, holding the window switch in the Up position for an additional five seconds.
18. Verify proper operation.