Pressurizing piston unit, task - GF42.45-P-4200-01A
WARNING: This page does not describe the selected car, but rather 42 other vehicles, including the 1999 Mercedes-Benz S600, 1999 Mercedes-Benz S500, 1999 Mercedes-Benz S420, 1999 Mercedes-Benz S320, and 1999 Mercedes-Benz CL600. However, it is still accessible from the selected car via links, so may be relevant.
The pressurizing piston unit is a hydraulic connecting component in the brake circuits between the tandem master brake cylinder and the ESP hydraulic unit.
With ESP control, the pressurizing piston unit separates the hydraulic connection between the master brake cylinder and hydraulic unit. It leads the pressurizing pressure to the two high-pressure pumps/return pumps in the hydraulic unit via the pressurizing piston valve control.