Power Brake Assist: Description and Operation

- The power brake booster reduces the effort required to push the brake pedal to apply the brakes.
- The vacuum booster hose supplies vacuum to the brake booster.
- The vacuum booster check valve closes when the engine is turned "OFF" and traps engine vacuum in the power brake booster.
- Refer to Brakes - System Diagnosis for diagnosis and testing of the power brake booster. Testing and Inspection