Xenon light control unit, component description - GF82.10-P-2119GZ
MODEL 164.1/8, 251.0/1 as of 9.7.07 with CODE (615) Bi-xenon headlamp unit with integrated curve illumination up to Model Year 2008
Shown on model 164.8
Location
The xenon headlamp control unit is installed under the particular lamp unit.
Tasks
- Output control of the left bi-xenon lamp with integral ignition module (E1e10) and of the right bi-xenon lamp with integral ignition module (E2e10)
- Control of the left headlamp range adjustment motor (E1m1) and the right headlamp range adjustment motor (E2m1) for implementing the automatic headlamp range adjustment (HRA [LWR])
- Control of the left dynamic curve illumination motor (E1m2) and the right dynamic curve illumination motor (E2m2) for implementing the active curve illumination
Function
The xenon headlamp control units work as a master/slave combination. The master function (front left lamp unit) and slave (front right lamp unit) are assigned by the different connector assignment and coding at the control unit connector.
After they have been connected to the lamp units, the xenon headlamp control units recognize the side of the vehicle where they were mounted and thus assume their function.
The xenon headlamp control units communicate via the Controller Area Network bus class C (engine compartment) (CAN-C).
Incoming information is processed, evaluated and relayed accordingly to the xenon headlamp control unit on the front right lamp unit by the xenon headlamp control unit on the front left lamp unit.
The xenon headlamp control units can be diagnosed.
Power control of the xenon bulb
When switching on the low beam function, the bi-xenon lamps are activated by the corresponding xenon headlamp control unit via an ignition auxiliary voltage.
For their part, the integrated ignition modules ignite the xenon bulb via a high-voltage surge. If an electric arc of sufficient stability is detected, the xenon headlamp control units switch over to the output-limiting operation.
Actuation of automatic headlamp range adjustment (HRA [LWR])
In order to correct the range of the bi-xenon lamp with integrated ignition module, the xenon headlamp control units must
- calculate the body pitch angle from the positions of the axes
- correct the angle of the projection mode as a function of the body pitch angle
- evaluate the vehicle speed for the operating mode switch (static mode, dynamic mode)
Controlling the active curve illumination
The active curve illumination is achieved by swiveling the bi-xenon lamps horizontally.
The xenon headlamp control unit actuates the left dynamic curve illumination motor, the xenon headlamp control unit actuates the right dynamic curve illumination motor.
The extent to which the headlamp units are swiveled in the process depends on various vehicle dynamics parameters.
Signal inputs and outputs
Discrete inputs
- Circuit 15
- Circuit 56b
- Circuit 31
- Front right level sensor (B22/9) and rear right level sensor (B22/10) (only at the right xenon headlamp control unit and without code (489) AIRmatic (air suspension with level adjustment and adaptive damping system ADS))
Discrete outputs
- Voltage supply for bi-xenon lamps
- Headlamp range adjustment motors
- Dynamic curve illumination motors
- Voltage supply for front right level sensor and rear right level sensor (only at the right xenon headlamp control unit and without code (489) AIRmatic (air suspension with level adjustment and adaptive damping system ADS))
Communication between the xenon headlamp control units, the headlamp range adjustment motors and the dynamic curve illumination motors takes place via the local interconnect network (LIN).
After replacement, the xenon headlamp control units must be coded to match the vehicle model and national version. The functions of the xenon headlamp control units are also programmed (specific to the country) via diagnosis.