Active brake booster (hybrid vehicles)

WARNING: This page is about a different car, the 2010 Mercury Mariner and 2010 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

The active brake booster uses vacuum supplied by an engine-mounted electronic vacuum pump and is similar to a conventional vacuum assist brake booster with the addition of a brake booster (vacuum) solenoid, a brake booster travel sensor and a vacuum sensor. If it is necessary to apply the friction brakes, the ABS module will send a signal to the brake booster solenoid that is proportional to the amount of brake torque requested. The booster solenoid will open to allow vacuum to draw the booster diaphragm and push rod towards the master cylinder piston, building hydraulic pressure. The brake booster vacuum sensor is used by the ABS module to monitor vacuum maintained inside the brake booster. The brake booster travel sensor is used to monitor the performance of the brake booster.