Brake Signal: Description and Operation

Typical Brake Pedal Position Switch:

PURPOSE
The Brake On-Off (BOO) switch detects braking action (deceleration). In response to the BOO signal, the Powertrain Control Module (PCM) modifies idle speed, air/fuel ratio, torque converter clutch operation on A/T applications, and A/C compressor (if equipped).


OPERATION
Switch contacts are closed when the brakes are APPLIED.