LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Audi >> 2021 >> A4 Quattro Premium Plus, 2.0L Eng VIN B >> Repair and Diagnosis (Single Page) >> Brakes >> Mechanical - Hydraulic >> Hydraulic Components (Brake System) (2 Of 2) >> 47 Hydraulic Components >> Brake Booster/Brake Master Cylinder >> Note

Brake Booster/Brake Master Cylinder: Note

WARNING:

Make sure that the actuator pin -15- for the brake lamp is pushed in the brake master cylinder -2- before installing the brake master cylinder -2-. If the actuator pin -15- is missing the brake lamp will not function.

Fig 1: Exploded View Of Brake Booster/Brake Master Cylinder
GWWA47-10230Courtesy of AUDI OF AMERICA, LLC

The actuator pin must always be pushed in the hole in the brake master cylinder directly on the Brake Lamp Switch -F-.

The actuator pin must not be bent or broken.

If this pin is missing or is damaged, the brake lamp will not function.

The actuator pin function is only for the brake lamp.

If the actuator pin is bent, broken or missing, then the brake booster must be replaced.