Brake Vacuum Sensor

WARNING: This page is about a different variant/trim than selected.

Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC

The brake vacuum sensor in the brake booster monitors the vacuum in the brake booster. This makes sure that sufficient vacuum is available in the brake booster during auto stop/start operation.

The brake vacuum sensor is mounted to the brake booster and hardwired to the Anti-lock Brake System (ABS) control module.

If the brake vacuum is less than a set threshold while auto stop/start is enabled, the Powertrain Control Module (PCM) either:

Restarts the engine to increase the vacuum in the brake booster.
Inhibits the engine shutting down, if insufficient vacuum in the brake booster.

For example, when the driver repeatedly presses the brake pedal while the engine is shutdown during an auto stop/start stop. This decreases the available vacuum in the brake booster and when the vacuum decrease to less than the set threshold, initiates an engine restart.

If a fault develops with the brake vacuum sensor a Diagnostic Trouble Code (DTC) is logged in the PCM.