GF42.45-P-3700C ESP control mode, function

GF42.45-P-3700C ESP control mode, function
- with CODE (472a) Electronic Stability Program (ESP)

Brake intervention to stabilize the vehicle is introduced by the ESP control module.

At the start of ESP control the switchover solenoid valves (y24 and y25) are switched to the <> (closed) and the high pressure and return pump (ml) is actuated. The BAS solenoid valve (A7/7y1)in the brake booster for (A7/7) is actuated (opened). This leads atmospheric pressure to the back of the diaphragms in the brake booster, generating pressure of approx. 6 bar which is applied as pilot pressure at the suction sides of the high pressure and return pumps (p1) p2)

Generally there is no ESP control at speeds < 10 km/h.

Component Identification:

At the end of the pressure reduction phase the system pressure (approx. 150 bar) between the self-priming high pressure and return pump (p1) switchover solenoid valve (y24) and solenoid valve y12) is initially led to both brake calipers of the circuit after the high pressure and return pump (ml) is switched off.

This prevents the system pressure in the tandem master brake cylinder being released suddenly and the noise build-up associated with this.