Grand Cherokee 4WD V8-4.7L VIN N (2000)
Brake Light Switch: Description and Operation
BRAKE SWITCH - PCM INPUT
When the brake light switch is activated, the Powertrain Control Module (PCM) receives an input indicating that the brakes are being applied.
After receiving this input, the PCM maintains idle speed to a scheduled rpm through control of the Idle Air Control (IAC) motor. The brake switch
input is also used to disable vent and vacuum solenoid output signals to the speed control servo.
