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.
Control Modules In The Rear Doors
The control modules in the rear doors are designated the left rear door module (LDM) (3/128) and right rear door module (RDM) (3/129). The control modules have control panels for the window lift mechanisms.
The rear door control modules use serial communication with the front door control module on the same side of the car.
The rear door control modules are directly connected to the lock motor in each door. The door control modules lock and unlock the door on receipt of a command from the front door control module.
The rear door control modules forward the status of the lock motors for child-proof and central locking to the relevant front door control module.
The control modules are powered via the rear fuse box.
Use the Manual With the Right Hardware
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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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