Informing and Warning

The system can only generate information or a warning reliably, if the road speed is greater than 50 km/h (31 mph). The function will work at speeds under 50 km/h (31 mph), but not with the high quality and reliability required by BMW. In order not to compromise on the satisfaction of discerning BMW customers, no information or warnings are issued at speeds below 50 km/h (31 mph).

Information is the first stage of assistance that the driver receives from the Active Blind Spot Detection system. The idea is to discreetly make the driver aware of a danger that could arise if he were to change lanes. Information is produced by discreetly illuminating a yellow triangle-shaped warning light in the housing of the door mirror. The warning light is only activated on the side of the vehicle where the necessity for a warning has been detected by the master radar sensor.

Thanks to this concept, the system provides assistance to the driver as early as the preparation phase of a lane change maneuver. The driver can glance briefly in the direction of the door mirror at any to collect information from the Active Blind Spot Detection system as to whether or not a danger exists regarding a lane change.

The discreet manner of the information, on the other hand, does not cause annoyance if the driver wishes to continue to drive straight ahead without making a lane change.

The ICM control unit sends a bus signal that contains a warning request indicating in which door mirror the warning light should light up and with which intensity. In the process, the ICM control unit selects an intensity that is dependent on the surrounding brightness. To do this, it reads a bus signal from the rain/lights/solar/condensation sensor and evaluates it.

The warning request from the ICM control unit travels via the central gateway module to the footwell module, where the signal is routed to the door mirror(s) concerned.

The information is issued to the driver in all cases where all of the following conditions have been satisfied:

The Active Blind Spot Detection system is switched on
The road speed is above 50 km/h (31 mph)
The master radar sensor has detected a necessity for a warning.

The second stage, the warning, should, in comparison, be significantly more prominent than the information. It should reach the driver quickly and directly, if he is still intending to make a lane change despite an impending dangerous situation.

The warning is issued, if the following conditions have been satisfied

The conditions for information have been satisfied:
The turn signal is switched on the side of the vehicle where the master radar sensor detected a necessity for a warning.

The steering column switch cluster issues the signal about the status of the turn signal via the FlexRay to the ICM control unit.

The only difference in the criteria for information and a warning is thus the status of the turn signal. The rear traffic situation or your own driving conditions do not influence it.

The visual aspect of the warning is generated by the respective warning light flashing with a high light intensity. In addition, the steering wheel begins to vibrate.

NOTE: If the driver changes lanes without using the turn signal, he will only receive the information discreetly from the Active Blind Spot Detection system. The Active Blind Spot Detection system only sends out the more intensive warning, if the driver has switched on the turn signal when he intends to make a lane change.