HBA Diagnosis

Component arrangement






Function of individual components

1. Control module
The control module is installed on the passenger s side below the passenger s airbag unit. If the control module is replaced, the following points must be observed:

1. Coding of the vehicle type
2. Calibration of the control module
3. Adjustment of the headlights

If a new control module is installed, fault codes "6 Control unit coding error" and "7 Calibration not performed yet" are stored.

Remedy:
Start the automatic control module search and code the vehicle type. Then perform a calibration and then erase the fault memory. Adjust the headlights after calibration.

2. Main light switch
The HBA system is activated when the parking light is switched on (terminal 58). The headlights are set to high-beam position when the highbeam switch is operated.

3. Angle sensor for HBA, rear
The sensor is fastened on the left side of the rear axle and is connected to the lower axle strut by a linkage.
A sensor measures the compression travel and forwards this value as a sensor voltage to the control module.

4. Angle sensor for HBA, front
The sensor is fastened on the left side of the front axle and is connected to the axle strut by a linkage. A sensor measures the compression travel and forwards this value as a sensor voltage to the control module.

5. Headlights
Each headlight includes a stepper (servomotor for HBA) which is activated by the control module. Figure 407_99 (arrow) shows the connections for the respective servomotor.

Headlight without lens