System Component Description

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The brake assist system consists of the following:

Brake Pedal: Receives, multiplies and transfers brake system input force from driver.
Brake Pedal Pushrod: Transfers multiplied input force received from brake pedal to brake booster.
Supplemental Brake Assist: The Supplemental Brake Assist (SBA) unit creates vacuum for the brake booster in case of a vacuum loss or low vacuum to the brake booster.
Vacuum Brake Booster: Uses source vacuum to decrease effort required by driver when applying brake system input force.
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: Supplies force used by vacuum brake booster to decrease brake pedal effort.
Vacuum Source Delivery System: Enables delivery and retention of source vacuum for vacuum brake booster.