BMW 7 Series: Visual Alarm/Feedback

Central locking system

The Car Access System outputs signals for the central locking system function. The footwell module also receives the signals via the K-CAN2 and uses them for visual feedback of the central locking system.

Antitheft alarm system

The footwell module enables the anti-theft alarm system to trigger the visual alarm via the direction indicator lights.

The roof functions center with integrated ultrasonic interior movement detector makes available the signal for the visual alarm via the K-CAN2. Furthermore, the footwell module receives the signals from the roof functions center for visual feedback of the anti-theft alarm system.

Crash signal

The footwell module switches on the hazard warning lights and the interior lighting when the crash safety module sends a crash signal. The hazard warning lights can be switched off with the hazard warning light switch.

The light in the hazard warning light switch is switched off by pressing the light switch to position 0 "Lights OFF" or by means of the rocker switch on the steering column stalk.

Special Case at "Terminal 15 OFF"

The exterior lighting would be switched off if "Terminal 15 ON" fails during vehicle operation or Terminal 15 is inadvertently deactivated by pressing the START-STOP button. The driving lights remain switched-on in order to maintain road safety in this situation. When the driving speed drops below 20 kph (12 mph), the low beam light is also switched off after a delay of approximately 30 seconds.

Emergency Operating Mode

Emergency operating mode is assumed if a defect occurs in the software of the footwell module that could cause failure of the entire exterior lighting system. In this case, the tail lights and the additional brake light are activated. This function is active as from "Terminal 15 ON".

Driving lights: Low beam headlight and one tail light on each side

Brake lights: Additional brake light and one tail light on each side

Adaptive Headlight

Adaptive headlight are an option and include the following functions:

• Adaptive headlight
• Turning lights
• Variable headlight beam pattern
• Adaptive headlight-range adjustment system.

The adaptive headlight were introduced with the E60. The F01/F02 therefore also includes, for instance, the functions variable headlight beam pattern or turning lights.

Furthermore, the adaptive headlight-range adjustment system is an additional function.

The light switch must be in the automatic driving lights control position.

Legal Regulation

Panning of headlights for the adaptive headlights is permitted within certain limits. An important point is that oncoming traffic is not to be dazzled by the headlights.

When the driver turns the steering wheel the vehicle moves on a circular track. The circular track is defined by movement of the wheels and the angle setting of the front wheels.

In order to avoid dazzling oncoming traffic, the break point of the headlight cut-off line must not lie on the left of the circular track within the distance of 100 times the headlight installation height.

The statement for the cut-off line refers to driving on the right. For driving on the left the statement for the cutoff line is mirror-symmetrical.

Fig. 57: Identifying Break Point Cut-Off Line For F01/F02

COMPONENTS DESCRIPTION CHART

1. Estimated circular track
2. Cut-off line break point
3. Steering angle

Preconditions for the Adaptive Headlight

To ensure its operability, the adaptive headlight must be adapted to the vehicle-specific data. The vehicle-specific data are located in the footwell module and in the headlight driver modules.

The footwell module contains the data:

• Vehicle identification number
• Vehicle type.

The headlight driver modules contain the data for:

• Headlight and headlight swivel range
• Permitted acceleration and deceleration ramps
• Characteristic speed maps
• Encoding
• Vehicle identification number
• Vehicle type.

The footwell module has the central responsibility for the adaptive headlight function. The entire software for the adaptive headlight is therefore located in the footwell module.

The footwell module is connected via the LIN bus for communication with the headlight driver modules.

The footwell module requests the current headlight status. The footwell module sends the requests necessary for panning the light from the headlights to the headlight driver modules via the LIN bus.

The footwell module is also still connected to the vehicle electrical and bus systems via the K-CAN2. Signals important for the function of the adaptive headlights are received by the footwell module via the K-CAN2.

The table below lists those control units that provide input signals.

K-CAN SIGNALS CHART

Bi-xenon Headlight

Each bi-xenon headlight contains following components:

• Bi-xenon control unit
• Swivel module for bi-xenon headlight
• Stepper motor for headlight vertical aim control
• Side light corona/daytime driving light corona
• Direction indicator lights
• Design light
• Side marker light
• Headlight driver module.

Bi-xenon Control Unit

The bi-xenon control unit is located on the bi-xenon headlights.

It supplies the power and ignition voltage for the bi-xenon light bulb.

Swivel module for bi-xenon headlight

Among other things, the swivel module contains following components:

• Bi-xenon lamp
• Hall sensor for zero position
• Stepper motor.

The bi-xenon light bulb is integrated in the swivel section of the adaptive headlight. The zero position Hall sensor registers the zero position of the swivel module.

The stepper motor provides the swivel movement of the swivel module. A separate stepper motor is installed for the headlight vertical aim control.

The headlight driver module controls and monitors the movement of the stepper motors for the adaptive headlights and the vertical aim control system.

Side lights/daytime driving light

The side lights/daytime driving light is designed as a fiber optics light guide ring. A 35 W bulb (H8) supplies the light to the fiber optics ring from below.

Switch-on Conditions

The adaptive headlight can be activated as from terminal status "Terminal 15 ON".

The rain/light/solar/condensation sensor sends the request to switch on the low beam headlights as soon as it detects low light levels (darkness). Initially, the footwell module switches on the headlight driver modules. The adaptive headlight is ready for operation following a reference run of the bi-xenon headlights.

NOTE: A reference run is performed during every new start.

The conditions for switching on the adaptive headlight are:

• "Terminal 15 ON"
• Light switch in automatic driving light control position
• Rain/light/solar/condensation sensor detects darkness
• Both bi-xenon headlights are intact.

NOTE: The footwell module detects a defective bi-xenon headlight by measuring the intake current of the respective bi-xenon headlight.

Switching on Adaptive Headlight

The adaptive headlight is switched on as soon as the rain/light/solar/condensation sensor sends the switch-on signal for the low-beam headlight.

Function Indicator

The low beam headlight and the headlight vertical aim control remain active in the case of fault. The swivel function of the bi-xenon modules is deactivated. A Check Control message is output on the instrument cluster.

Reference Run

In order to determine the zero position, the adaptive headlight performs a reference run depending on the current position of the swivel module.

To avoid a hysteresis during calibration, the swivel module always moves from the same side over the zero position sensor.

This is achieved in that the swivel module is always moved to the same side of the zero position sensor before switching off the adaptive headlight.

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