BAS brake booster, design - GF42.31-P-4000-01A

Fig 1: Locating BAS Brake Booster Components

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Vacuum-powered brake booster with one or two diaphragms. The BAS solenoid valve (y1) and the BAS release switch (s1) are permanently built into the BAS brake booster (A7/7) (cannot be changed). The BAS diaphragm travel sensor (b1) and, if necessary, the BAS control module (N48) are fitted onto the brake booster (can be changed).