BMW 7 Series: Headlight Driver Module
The headlight driver module controls and monitors the stepper motors for the adaptive headlights and the headlight beam throw adjustment system of the respective bi-xenon headlight.
The integrated chassis management makes available the values for the dynamic headlight beam throw adjustment system to the footwell module. The footwell module receives these values via the K-CAN2. In this way the beam angle can be adapted to the different driving situations, e.g. laden/unladen.
The signal from the integrated chassis management must be transferred to the KCAN2 in the central gateway module.
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Fig. 60: Headlight Driver Module Circuit
COMPONENTS DESCRIPTION CHART
- Stepper motor for adaptive headlight
- Headlight driver module
- Stepper motor, headlight vertical aim control
- Zero position sensor
- LIN-Bus
- Coding pin for right/left
- Voltage supply +
The headlight driver module fulfils the following functions:
- Receiving and evaluating the data sent from the footwell module via the
LIN-bus:
- Reference run
- Target position commands
- Diagnosis requests
- Output control of the stepper motors
- Zero position acquisition of swivel module
- Reference run of swivel module
- Position feedback of swivel module to footwell module
- Diagnosis
- Feedback of diagnosis data to the footwell module.
The footwell module in its function as the central control unit for the adaptive headlight checks the status of the headlight driver modules every 20 ms.
Furthermore, the footwell module initiates activation of the LEDs in the front headlights.
Zero Position of Swivel Module
The zero position of the swivel module is determined by the zero position sensor. The zero position sensor is a Hall sensor. The falling edge of the Hall sensor is evaluated to determine the zero position. The zero position corresponds to exactly the position of the swivel module in the straight-ahead position of the vehicle.
The headlight driver modules prepare the data for data transfer via the LIN bus. The footwell module requests the data from the headlight driver modules.
NOTE: The sensor signal can be read out during diagnosis.
The sensor is defective if no sensor signal is applied.
Switch-off Conditions
As from "Terminal 15 OFF", the footwell module sends the request via the LIN bus to assume the rest position of both swivel modules to the headlight driver modules. On reaching the rest position of the swivel modules, the headlight driver modules send a confirmation to the footwell module. The headlight driver modules also activate the side lights function.
Afterunning Time
The afterunning time is 2 seconds.
Check Control Message
The Check Control messages below exist for the adaptive headlights and the beam throw adjustment system.
CHECK CONTROL MESSAGE CHART
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Turning Lights
The turning light function is available only in connection with the option
Adaptive Headlight. In addition to the
adaptive headlights, the turning light additionally illuminates the area in
front of
Service Information
Adjusting Headlights
The same procedure as before can be adopted for adjusting the lights. On a
vehicle with the adaptive headlights
optional extra the light switch must be in position "2".
If the l
SEE MORE:
Replacing Inside Light
Unclip cover (1) at side recess (arrowed) and remove towards bottom.
Fig. 196: Locating Cover Side Recess
Unclip lamp housing (1) at side recess (arrowed).
Fig. 197: Locating Lamp Housing Recess
Disconnect flat connector (1) from flat connector contact.
Fig. 198: Identifying Flat Connector
CAUTIO
Wiper system
General information
Do not use the wipers if the windshield is dry, as
this may damage the wiper blades or cause them
to become worn more quickly.
Safety information
Warning
If the wipers start moving in the folded away
state, body parts can be jammed or damage
may occur to parts of the vehicle. Th
