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GF42.45-P-2000SK ESP Brake Moment Control Circuit, Function



GF42.45-P-2000SK ESP brake moment control circuit, function

Normal mode
This is the case when the driving state requires no control mode. This mode also exists, if a fault exists in the Electronic Stability Program (Electronic-Stability-Program) (ESP), Brake Assist (BAS) or in the antilock brake system (ABS). Drive moment control is not activated.

ABS control mode
From wheel speed signals the ESP and BAS control unit (N47-5) detects that the criteria for an ABS control exist and the corresponding solenoid valves are actuated.

The solenoid valves are actuated individually (4-channel control).

ASR control mode
As soon as a drive wheel tends to spin, the ESP and BAS control unit (N47-5) actuates the corresponding rear axle solenoid valves.
ESP control mode

In the ESP and BAS control unit (N47-5) the signals of the wheel speeds, the steering angles, the yaw rate of the vehicle, the lateral acceleration as well as the brake pressures of the individual wheels are detected and processed by a drive condition controller. After the evaluation of input signals the required solenoid valves are actuated in order to regulate the brake pressure in the individual wheel brakes.

ESP-Off-operation (ESP OFF)
When the ESP OFF switch (A72/1s1) in the upper control panel control unit (N72/1) is pressed the ESP-drive torque control is switched off and in addition the ESP stability function is canceled when accelerating and in the case of coasting. The ESP stability function remains operational during braking. EBR control is deactivated. With the switch in this position, braking force is applied to one spinning drive wheel via the braking moment control circuit at vehicle speeds of up to 40 km/h. In addition if cut-in conditions are present, brake intervention is retained up to a maximum of 60 km/h. The braking torque, however, is gradually reduced.

BAS mode
From the pedal speed of the brake pedal the ESP and BAS control unit (N47-5) detects that an emergency case braking exists and introduces BAS-mode.