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 Headlight Leveling
Position sensors (7/120-121) on the rear and front wheel suspensions send information to Headlamp Control Module (HCM) (4/114) about the vehicle's angle depending on load conditions, acceleration, and braking.
Headlamp Control Module (HCM) uses information from the position sensors to calculate current angle for the headlights.
For vehicles with active headlights and GDL-lights, Headlamp Control Module (HCM) sends information bout current angle to Left headlamp control unit (LHCU) and Right headlamp control unit (RHCU) via serial communication.
The actuators are controlled from Left headlamp control unit (LHCU) and Right headlamp control unit (RHCU).
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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