Antilock Brakes / Traction Control Systems

Pressure Reservoir Charging:

NORMAL OPERATION

Operation during pressure reservoir charging

Pressure Increase:

PRESSURE INCREASE

Left rear wheel solenoid valve (y3) is in position "0." This way the brake fluid arrives directly at the left rear brake caliper (6b) at full reservoir pressure.

Pressure Release:

PRESSURE RELEASE

Pressure Left rear wheel solenoid valve (y3) switches to position "2." The pressure connection closes. The brake caliper (6b) is connected with the ASR return/pressure pump (m1) through the left rear wheel solenoid valve (y3). Brake fluid flows from the brake caliper into the pressure accumulator (11), through the pump inlet valve (8), into and past the noise damper (10) to the pressure circuit upstream of solenoid valves (y3 and y4) and through switchover solenoid valve (y5) back to the pressure reservoir (13). In this way, the control sequence can be repeated an unlimited number of times reducing the pressure in the pressure reservoir.

Presure Retention:

PRESSURE RETENTION

Left rear wheel solenoid valve (y3) switches to position "l." All connections at the solenoid valve are closed. Brake pressure remains constant in the brake caliper.