GM Service Manual Online
For 1990-2009 cars only

Proportioning Valve Description for Chevrolet Prizm 1999

The proportioning valve is located on the vehicle cowl behind the engine.

The proportioning valve limits the outlet pressure to the rear brakes after a predetermined master cylinder pressure is reached. This feature is used when less rear apply force is needed. This feature performs the following functions:

    • Allows smooth braking action
    • Reduces the chances of rear wheel lockup during normal braking