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.
System functions
The adaptive headlights system adjusts the horizontal aim of the headlights (i.e. from side to side) in order to illuminate the inside of a bend when cornering.
The following functions of the adaptive headlights system are described below:
- System activation and calibration sequence
- Activation of stepper motor controllers (SMC)
- Speed-dependent analysis of input signals
- Horizontal swivelling of the headlights by the stepper motor controller
- Deactivation of adaptive headlight movements under extreme driving
- Deactivation of adaptive headlight movements in response to system faults
- Setting headlights to parked position
- Activation of automatic headlight-range adjustment by the AHL control unit
- Adaptive headlights for automatic driving lights control
System activation and calibration sequence
When terminal 15 is switched ON, the headlights always perform a calibration sequence, even if the lights are not switched on. The AHL control unit sends the "perform calibration sequence" request to the stepper motor controllers (SMC = control unit for the headlight stepper motors). The stepper motor controllers actuate the stepper motors in the headlights. The calibration sequence is performed. During the calibration sequence, the headlights move in the following manner:
- The headlights move horizontally (= calibration sequence for the adaptive headlights ).
- The headlights move vertically (= calibration sequence for the headlight-range adjustment function).
- At the end of the calibration sequence, the headlights are in the straight-ahead position.
Following the calibration sequence, the system is ready for operation.
When reverse gear is engaged, the headlights are moved to the straight-ahead position.
If terminal 15 is switched on and off repeatedly (for example, for demonstration reasons), the headlights are not calibrated each time terminal 15 is switched on.
Terminal 15 must have been switched off for at least 15 seconds before it is switched on. Only then is a calibration sequence performed when terminal 15 is switched on again.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.