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.
Activating Components And Functions
This function can be used to activate components and functions which affect the outputs of the central electronic module (CEM).
The following components can be activated:
- deactivation of the relay for extended power supply
- activating the relay for extended X2 supply
- activating the relay for the park neutral position (PNP) switch
- activating the relay to raise the rear left-hand window
- activating the relay to lower the rear left-hand window
- activating the relay to raise the rear right-hand window
- activating the relay to lower the rear right-hand window
- activating the relay for high beam
- activating the relay for low beam
- activating the spot lamp relay (accessory)
- activating the relay for the parking lamps
- activating the relay for the daytime running lamps
- activating the relay for the front fog lamps
- activating the relay for the windscreen wipers off/on
- activating the high speed windscreen wiper relay
- activating the relay for the front washer motor
- activating the relay for the headlamp washer
- activating the relay for the horn
- activating the frequency signal from the engine control module (ECM) for the fuel pump (FP) relay
- activating the speed signal (for accessories)
- activating the signal to the switch for the hazard warning signal flashers. To switch off the hazard warning signal flashers, they must be activated and reset again. The function is switched off if the button in the car is pressed once
- activating the key ring lighting (the key ring lighting does not light if the car is locked. The window can be open however, to allow communication with the data link connector (DLC))
- activating the signal for the alarm LED
- activating the pulse width modulated signal for the courtesy lighting
- activating the relay for preheating the leak diagnostic pump
- activating the infotainment relay.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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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