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GF42.47-P-0001TM Adaptive Brake (ABR), Function



GF42.47-P-0001TM Adaptive brake (ABR), function

Function of Adaptive Brake (ABR)
ABR assists the driver in dangerous situations which occur suddenly and thus serves active safety.

ABR contains the following functions:
^ Antilock brake system (ABS)
^ Acceleration Slip Regulation (ASR)
^ Electronic stability program (ESP)
^ Brake Assist (BAS)
^ Electronic brake force distribution (EBV)

as well as the additional functions:
^ HOLD
^ Precharging
^ Dry braking
^ Adaptive stop lamp flashing (ECE only)

The ESP control unit (N47-5) evaluates the data from the following components for recording the current driving situation:
^ Yaw rate and lateral acceleration sensor (B24/15)
^ Left front rpm sensor (L6/1)
^ Right front rpm sensor (L6/2)
^ Left rear rpm sensor (L6/3)
^ Right rear rpm sensor (L6/4)
^ Steering angle sensor (N49)

ABS
ABS prevents the wheels locking when braking and as a result maintains the steerability and directional stability and road adhesion during the vehicle deceleration.

ASR
ASR prevents the drive wheels from spinning while driving. It also causes improved directional stability and road adhesion with increased traction potential over the entire vehicle speed range.

ESP
ESP prevents breakaway when the vehicle oversteers or understeers. It ensures (within the framework of physical limits) that the vehicle does not deviate from the course specified by the driver. Brake forces are produced selectively at the individual wheels to correct any deviations. Furthermore, torque is reduced to increase the directional stability and road adhesion.

BAS
BAS detects emergency braking situation by means of a rapid brake pedal operation and increases the brake pressure if necessary.

EBD (Electronic brake force distribution)
EBV [electronic brake force distribution] assists the driver in the partial braking range. It prevents overbraking of the rear axle and increases the vehicle stability in the curve, the pressure at the rear wheel on the inside of the curve being reduced or the pressure at the front wheel on the outside of the curve being increased if necessary.

Hold
HOLD assists the driver when starting off on a hill or during waiting times in traffic. HOLD is activated by briskly continuing to depress the brake pedal when stationary. The adjusted brake pressure is held until the driver quickly depresses the brake pedal again or starts off.

With USA and CDN the additional function HOLD is deactivated by coding in the ESP control unit. This takes place through the coding information from the central gateway control unit (N93).

Precharging
Precharging already builds up the brake pressure when the accelerator pedal is released suddenly, in order to reduce the response time during braking which may follow (e.g. by BAS).

Dry braking
Dry braking assists the performance of the brake in the wet. By applying the brake linings in cycles the water film is wiped off the brake disk. This improves the response time of the brake.

Adaptive stop lamp flashing (ECE)
In order to display to the following traffic that the driver has performed a panic braking, in such situations the stop lamp is actuated flashing and when the vehicle is stationary the hazard warning system is switched on automatically.