Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Rear Window Lift Mechanisms/Child Lock
The rear window lift mechanisms are operated using switches (3/85-86) in the door panels. Relays 2/116 or 2/118 for the left-hand side and relays 2/117 or 2/119 for the right-hand side are activated in the central electronic module (CEM) (4/56) depending on whether the window is to move up or down.
When the window lift mechanisms are operated from the driver's position, data is transmitted from the driver's door module (3/126) via the control area network (CAN) to the central electronic module (CEM) which transmits a signal to the correct relay.
There is a switch in the driver's door module (DDM) to allow for child locking, where the windows can only be operated from the driver's position. When this is active, data is transmitted via the control area network (CAN) to the central electronic module (CEM) to disconnect relay 2/120. This breaks the circuit for the rear switches.
When the child lock is activated, the lighting in the rear switches goes out.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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