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.
Automatic range adjustment (Bi-Xenon)
There are two motors, one on each headlamp, which angle the headlamps upwards or downwards to control the range of the beam. The motors are on the rear of the headlamps.
The motors are controlled by signals from a position sensor at the rear axle. The sensor detects the angle of the car under different load conditions and sends this information via the rear electronic module (REM) so that the central electronic module (CEM) can determine whether the lamps need to be raised or lowered.
There are diagnostics for the headlamp range adjustment.
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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