Main-Beam Assistant
63 01 05 (140)
Main-beam assistant E60/E61/E63/E64/E65/E66/E70/E90/E91/E92/E93
Introduction
The main-beam assistant assists the driver to operate the main-beam headlights. The main-beam assistant automatically switches the main-beam headlights on and off as the traffic situation changes.
The main-beam assistant detects vehicles travelling ahead of the car and oncoming traffic, and it also detects lighted stretches of roadway. By automatically switching off the main-beam headlights in good time, the main-beam assistant ensures that the occupants of oncoming vehicles, for example, are not dazzled by the headlights.
Advantages:
Drivers do not have to concern themselves with the job of operating the main-beam headlights. This enhances the level of convenience for drivers. The main-beam headlights are switched on more frequently by the main-beam assistant than is the case with manually operated main-beam headlights. The driver's field of vision is optimally illuminated. Driving in the dark, therefore, is rendered safer.
Important: The driver retains full responsibility for all his/her actions, despite the assistance of the main-beam assistant.
The main-beam assistant merely assists the driver in the task of operating the main-beam headlights.
Responsibility for switching the main-beam headlights on and off in accordance with the dictates of the traffic situation rests with the drivers.
The main-beam assistant can be deactivated at any time with the turn-signal/main-beam switch.
Option 5AC "Main-beam assistant" is available for the BMW 3, 5, 6 and 7-Series.
> - E60, E61, E63, E64, E65, E66 -
> - E90, E91, E92, E93, E70:
Note: Only the main beam of the bi-xenon headlights are switched on.
If a main-beam assistant is fitted, only the main beam of the bi-xenon headlights are switched on.
The halogen headlights are switched on only when the headlight flasher is actuated. In countries in which daytime driving lights are required by law, the halogen headlights are used for the daytime driving lights.
Brief description of components
The following components and control units provide input signals for the main-beam assistant:
- Light switch
The main-beam assistant can be activated only when the light switch is in position "A".
"A" stands for "automatic headlight control".
[for further information, please refer to SI Technology (SBT) 63 02 03 007]
- Turn-signal/main-beam switch
The main-beam assistant is activated and deactivated by mans of the turn-signal/main-beam switch.
See the section entitled "Operation" below.
[for further information, please refer to SI Technology (SBT) 63 02 03 007]
- Rain-light sensor
The rain-light sensor measures the brightness of the ambient light. The light module switches the dipped headlights on when daylight fails.
The main-beam assistant can be activated only when the dipped headlights are on. The precondition is that the light switch must be in the "A" position.
[for further information, please refer to SI Technology (SBT) 63 02 03 007]
- Wheel-speed sensors
Each of the wheel-speed sensors measures the circumferential speed of an individual wheel. The DSC control unit (DSC: Dynamic Stability Control) uses these input signals to calculate the car's road speed.
The main-beam headlights are switched on when the car's road speed is above 50 km/h.
The main-beam headlights are switched off when the car's road speed is below 38 km/h.
[for further information, please refer to SI Technology (SBT) 34 01 05 126]
- DSC sensor
The DSC sensor registers lateral acceleration and calculates the yaw rate.
("Yaw" is the movement of the vehicle about the vertical axis, e.g. when the car is cornering).
The main-beam assistant uses the yaw rate to improve evaluation when the car corners. The DSC sensor is underneath the driver's seat. For safety reasons, cars with active front steering have a second DSC sensor underneath the front passenger's seat.
[for further information, please refer to SI Technology (SBT) 34 02 03 042]
- Image sensor
The image sensor is a special camera for detecting light sources.
The image sensor transmits images to the control unit for the main-beam assistant.
The images are carried by an LVDS data line (LVDS: Low Voltage Differential Signalling).
The control unit for the main-beam assistant analyses the images.
The image sensor and the control unit are installed in a common housing and can only be supplied as a unit.
- Reverse gear switch
The main-beam headlights are not switched on if reverse gear is engaged.
In a manual-shift car, the reverse gear switch supplies the "reverse gear engaged" information.
The reverse gear switch sends this information to the light module.
- Selector lever position switch
The main-beam headlights are not switched on if reverse gear is engaged.
In a car fitted with electronic transmission control (EGS), the selector lever position switch supplies the "reverse gear engaged" information. The selector lever position switch sends this information to the EGS control unit. The EGS control unit sends this information to the light module or footwell module.
- Selector angle sensor and shift travel sensor
> E60, E61, E63, E64, E65, E66
The main-beam headlights are not switched on if reverse gear is engaged.
In a car fitted with sequential manual transmission (SMG), the selector angle sensor and the shift travel sensor supply the "reverse gear engaged" information. The selector angle sensor and the shift travel sensor send the information to the SMG control unit. The SMG control unit sends the information to the light module.
The following control units are involved in the main-beam assistant system:
- FLA: Main-beam assistant
The FLA control unit analyses the images from the image sensor. The FLA control unit receives information on road speed and yaw rate from the DSC control unit.
The FLA control unit sends a switch-on recommendation or a switch-off recommendation for the main-beam headlights to the light module. The recommendation depends on the traffic situation, the ambient light, and the car's road speed.
The FLA control unit is connected to the K-CAN.
- LM: Light module
> E60, E61, E63, E64, E65, E66
The light module receives various input variables for the main-beam headlights:
- Switch-on or switch-off recommendation from the FLA control unit
- Switch position of the light switch
- Switch position of the direction indicator/mean-beam switch
- Information from the reverse gear switch or the selector lever position switch or the selection angle and shift travel sensor
- Information from the rain-light sensor, as to whether the dipped headlights have to be switched on
On the basis of the input variables, the light module decides whether the main-beam headlights should be switched on or off.
- The light module actuates the bi-xenon headlights.
- The light module actuates the FLA indicator light in the instrument cluster.
A Check-Control symbol appears if the main-beam assistant fails.
The light module is connected to the K-CAN.
> Light module E60, E61, E63, E64 [for further information, please refer to SI Technology (SBT) 63 02 03 007]
> Light module E65, E66: [for further information, please refer to SI Technology (SBT) 63 02 03 007]
- FRM: Footwell module
> E90, E91, E92, E93, E70
The footwell module receives various input variables for the main-beam headlights:
- Switch-on or switch-off recommendation from the FLA control unit
- Switch position of the light switch
- Switch position of the direction indicator/mean-beam switch
- Information from the reverse gear switch or selector lever position switch
- Information from the rain-light sensor, as to whether the dipped headlights have to be switched on
On the basis of the input variables, the footwell module decides whether the main-beam headlights should be switched on or off.
- The footwell module actuates the bi-xenon headlights.
- The footwell module actuates the FLA indicator light in the instrument cluster.
A Check-Control symbol appears if the main-beam assistant fails.
The footwell module is connected to the K-CAN.
[for further information, please refer to SI Technology (SBT) 61 04 04 094]
- DSC: Dynamic Stability Control
The DSC control unit calculates the car's road speed using the signals from the wheel-speed sensors. The DSC control unit sends the information on road speed to the main-beam assistant.
The DSC control unit also sends the information from the yaw-rate sensor in the DSC sensor to the main-beam assistant.
> DSC 8: [for further information, please refer to SI Technology (SBT) 34 02 03 042] Dynamic Stability Control DSC 8
> DSC Mk60E5: [for further information, please refer to SI Technology (SBT) 34 01 04 107]
> DSC 8Plus: [for further information, please refer to SI Technology (SBT) 34 01 05 126] Dynamic Stability Control 8Plus
- EGS or SMG: Electronic gearbox control or sequential manual transmission
The EGS control unit receives the "Reverse gear engaged" information from the selector lever position switch. The EGS control unit is connected to the PT-CAN.
[more in SI Technical (SBT) 24 01 03 040]
The SMG control unit receives the "Reverse gear engaged" information from the selector angle sensor and the shift travel sensor. The SMG control unit is connected to the PT-CAN.
[for further information, please refer to SI Technology (SBT) 23 03 03 044]
- SZL: Steering Column Switch
The switch signals from the turn-signal/main-beam switch are picked up and evaluated by the SZL control unit. The SZL control unit sends the position of the turn-signal/main-beam switch to the light module (E60, E61, E63, E64, E65, E66) or footwell module (E90, E91, E92, E93, E70)
> SZL E60, E61, E63, E64, E65, E66: [for further information, please refer to SI Technology (SBT) 63 02 03 007]
> SZL E90, E91, E92, E93, E70: [for further information, please refer to SI Technology (SBT) 61 07 04 103]
The following components are controlled:
- Bi-xenon headlights
The bi-xenon headlights are actuated by the light module.
[for further information, please refer to SI Technology (SBT) 63 02 03 007]
Note: Only the main beam of the bi-xenon headlights are switched on.
If a main-beam assistant is fitted, only the main beam of the bi-xenon headlights are switched on. The halogen headlights are switched on only when the headlight flasher is actuated. In countries in which daytime driving lights are required by law, the halogen headlights are used for the daytime driving lights.
- Instrument cluster
The indicators in the instrument cluster are as follows:
- Main-beam indicator lamp (legally stipulated, blue)
- FLA indicator light
- Orange on BMW 3, 5 and 6-Series and on X5
- Blue on BMW 7-Series
- Check-Control symbol for failure of the main-beam assistant (yellow)
See the section entitled "System functions" below.
The following components provide the power supply for the main-beam assistant:
- PM: Power module
> E65, E66
In the BMW 7-Series, the power module supplies power to the main-beam assistant.
- Rear power distributor
> E60, E61, E63, E64
In the BMW 5-Series and 6-Series, the rear power distributor supplies power to the main-beam assistant.
- Power distributor in junction box
> E90, E91, E92, E93
On the BMW 3-Series, the power distributor in the junction box supplies voltage to the main-beam assistant.
- Rear power distributor
> E70
On the BMW X5, the rear power distributor provides power to the main-beam assistant.
System functions
In accordance with the traffic situation, the FLA control unit sends a switch-on recommendation or a switch-off recommendation for the main-beam headlights to the light module or footwell module. On the basis of this recommendation and various other the input variables, the light module or footwell module decides whether the main-beam headlights should be switched on or off.
The following system functions of the main-beam assistant are described:
- Automatic main-beam headlight switch-off when oncoming traffic is detected
- Automatic main-beam headlight switch-off when vehicle detected ahead of the car
- Automatic main-beam headlight switch-off when adequate ambient lighting is detected
- Automatic main-beam headlight switch-on
- Indicators in the instrument cluster
- Function limitations of the main-beam assistant
- Automatic alignment of the main-beam assistant
Automatic main-beam headlight switch-off when oncoming traffic is detected
The light cone of the main-beam headlights has a range of about 400 m. The image sensor can detect other light sources within a range of about 1000 m. This ensures that the image sensor detects oncoming vehicles before their drivers can be dazzled by the light cone of the main-beam headlights.
When the image sensor detects an oncoming vehicle, the FLA control unit sends a switch-off recommendation to the light module or footwell module. The light module or footwell module switches the main-beam headlights off.
Automatic main-beam headlight switch-off when vehicle detected ahead of the car
When the image sensor detects a vehicle ahead, the FLA control unit sends a switch-off recommendation to the light module or footwell module. The light module or footwell module switches the main-beam headlights off.
Automatic main-beam headlight switch-off when adequate ambient lighting is detected
When the image sensor detects an environment in which ambient lighting is adequate, the FLA control unit sends a switch-off recommendation to the light module or footwell module. The light module or footwell module switches the main-beam headlights off.
Adequate ambient lighting means:
- Daylight
- Twilight
- Street lighting (e. g. in illuminated towns)
Automatic main-beam headlight switch-on
If there is no reason for the lights to be dipped, the light module or footwell module switches the main-beam headlights on. The bi-xenon headlights are switched to full beam.
Displays in the instrument cluster
The FLA indicator light lights up in the instrument cluster as soon as the main-beam assistant is activated (blue on the BMW 7-Series, orange on the BMW 3, 5, and 6-Series and on the X5).
The main-beam indicator light also lights up (blue) in the usual way as soon as the main-beam headlights are switched on.
A Check-Control symbol appears (yellow) if the FLA control unit detects a system failure.
Function limitations of the main-beam assistant
The main-beam assistant can be subject to function limitations under the following circumstances:
- Inclement weather conditions (e.g. fog)
- Poorly lighted road users (e.g. cyclists, pedestrians)
- Certain road signs (e.g. the warning sign for a tight bend): Reflections from traffic signs may be incorrectly interpreted by the main-beam assistant as a vehicle driving ahead or as oncoming traffic.
- Driving over crests and through dips
- Certain traffic situations (e.g. tight bends, vehicles approaching from the side)
- Image sensor's field of view obstructed (e.g. by snow)
Automatic alignment of the main-beam assistant
In order to operate correctly, the image sensor must be aligned parallel with the vehicle's centerline. When the car is driven at night, the main-beam assistant can automatically correct alignment up to 3° to the left or 3° to the right. This correction compensates for minor deviations from the centerline.
Driving conditions for automatic directional orientation of the main-beam assistant are:
- Straight ahead for a distance of approx. 50 km: A relatively straight stretch accelerates the directional orientation.
- Road marking must be clearly visible.
Operation
Operation of the main-beam assistant is described in a separate section.
The following controls of the main-beam assistant are described:
- Switching on automatic headlight control
- Activating the main-beam assistant
- Deactivating the main-beam assistant
- Reactivating the main-beam assistant
- Switching on the headlight flasher
Preconditions for activation
For technical reasons, distinctions are drawn between the following conditions required for switch-on:
- Conditions required for switch-on for the FLA control unit
- Conditions required for switch-on for the main-beam assistant
- Conditions required for switch-on for the main-beam headlights
Conditions required for switch-on for the FLA control unit
The FLA control unit is active as of terminal 15 ON.
Conditions required for switch-on for the main-beam assistant
- Light switch set to position "A"
- Dipped headlights switched on.
When the switch is in position "A", the dipped headlights are switched on by the automatic headlight control.
- Turn-signal/main-beam switch pressed forward (in forward direction of travel).
Conditions required for switch-on for the main-beam headlights
- Road speed greater than 50 km/h.
- Reverse gear must not be engaged.
- Image sensor does not detect an oncoming vehicle or a vehicle ahead.
- Image sensor detects adequate darkness.
Notes for service staff
The following information is available for service staff:
- General note:
- Diagnosis:
- Encoding/programming: ---
Subject to change.