System Component Description

The brake booster vacuum assist system consists of the following:

Auxiliary Brake Booster Pump

The auxiliary brake booster pump is a secondary vacuum supply to the brake booster to maintain sufficient vacuum needed for brake assist.

Vacuum Brake Booster

Uses source vacuum to decrease effort required by driver when applying the brake.
When brake system input force is applied, air at atmospheric pressure is admitted to the rear of both vacuum diaphragms, providing a decrease in brake pedal effort required. When input force is removed, vacuum replaces atmospheric pressure within the booster.

Vacuum Source

Vacuum is supplied by engine vacuum or by the auxiliary brake booster pump.

Brake Booster Vacuum Sensor

The brake booster vauum sensor is mounted on the vacuum brake booster and provides feedback to the electronic brake control module relative to the amount of vacuum available for the vacuum brake booster. When the vehicle is equipped with Stop/Start System the brake booster vacuum sensor provides also feedback to the engine control module.