Brake Booster

Multiplies the effort the driver applies to the brake pedal. Traditionally driven by engine manifold vacuum, which is why a vacuum leak or a failed check valve turns up as a hard pedal — and why turbocharged engines, hybrids and electric vehicles, which cannot rely on manifold vacuum, increasingly use an electrically driven booster instead. Losing assistance is not losing brakes: the hydraulic path is unbroken and the car still stops, but the pedal becomes very hard and stopping distances grow considerably, because the driver is now supplying all the force.

Also known as: servo, brake servo, vacuum booster, ebooster, brake assist unit

Referenced by 92 codes

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Codes involving this component (92)

Other components in Braking, Steering and Suspension

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