GF42.31-P-4004RT BAS Brake Booster, Component Description

GF42.31-P-4004RT BAS brake booster, component description

Component Identification:

Location
The BAS brake booster is installed in the major assemblies compartment on the left.

Task
It boosts the force of the driver's foot while braking (like a conventional brake booster) and carries out the BAS brake application.

BAS brake booster (sectional drawing)

Component Identification:

An emergency stop is detected by the ESP control unit (N47-5) by means of the BAS diaphragm travel sensor. With BAS brake application, the BAS solenoid valve opens the poppet valve which then allows atmospheric pressure from the vehicle interior to pass through the air filter and to the rear side of the power diaphragms.

The full assistance pressure from the brake booster is transmitted to the master brake cylinder via the output rod. When brake application has ended, the ESP control unit receives a signal from the BAS release switch and the BAS solenoid valve closes again. The BAS assistance is terminated.