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.
Central electronic module (CEM)
Central electronic module (CEM) (4/56) is located behind the dashboard, beside the driver. The function of the central electronic module (CEM) in the central locking system is:
- to activate the direction indicators, as confirmation with locking and unlocking the central locking
- to send a command, to activate the acoustic signal in the driver information module (DIM) with the function for key warning
- to send a message to the rear electronic module (REM), on the type of key used to unlock the vehicle or the type of key for switching on the ignition. This is significant for activating and deactivating private locking.
- to forward the request for unlocking the fuel tank filler cover from the light switch module (LSM).
Central electronic module (CEM) communicates with the rear electronic module (REM) via the low-speed side of the CAN network.
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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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