Front Suspension

Vehicle level sensor in vehicles with automatic headlight range control





Vehicles with gas discharge lamps have automatic headlight range control as standard equipment.

The automatic headlight range control requires information regarding compression and rebound travel at the front and rear suspension in order to function correctly.

For this purpose the position of the lower left control arm in relation to the body is transferred to the left front level control system sensor G78 via a coupling rod. This transmits electrical signals to the control module for the headlight range control.

On the rear axle, the signals are transmitted to the control module by the left rear level control system sensor G76. These signals are required to determine the current height of the vehicle.

The automatic headlight range control reacts to changes in the suspension height (attitude of the vehicle).





The attitude of the vehicle can vary in the following situations:
^ Different load conditions; vehicle empty, vehicle partly or fully loaded
^ Slow or fast driving

CAUTION! Adjustment of headlights!

Note: The basic headlight setting must always be checked when:

^ The control arm has been removed or replaced Electrical Equipment On Board Diagnostic (OBD) Self-diagnosis of automatic headlight range control
^ Installation work has been performed on the vehicle level sensor
^ The vehicle level sender has been replaced
^ The retaining clip for the coupling rod on the control arm has been detached

Basic setting of headlights Electrical Equipment On Board Diagnostic (OBD).





1 - Bracket

2 - Hex nut, 8 Nm

3 - Left front level control system sensor-G78-
^ Checked electrically via On Board Diagnostic (OBD)

4 - Coupling rod from left front level control system sensor -G78-; tightening torque to component: 4 Nm - 3 -

5 - Control arm

6 - Hex bolt, 25 Nm

7 - Coupling rod
^ Adjustment dimension for bracket with elongated hole

8 - Hex nut, 4 Nm

9 - Connector

10 - Longitudinal member

11 - Pop-rivet bolt
The pop-rivet bolt can be installed with the pop rivet tongs V.A.G 1765B





Adjustment dimension for headlight range control linkage at bracket with elongated hole
Dimension a = 19 mm

Tighten nuts (M6) to 4 Nm.