RAM 1500 Truck 2WD V6-3.9L VIN X (1999)
Brake Light Switch: Description and Operation
Switch With RWAL System
SYSTEM OPERATION
Vehicles equipped with the speed control option use a dual function stop lamp switch. The switch is mounted on the brake pedal mounting bracket
under the instrument panel. The PCM monitors the state of the dual function stop lamp switch.
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 supply/deny power to the speed control servo solenoids.
