The automatic transmission shift lock control system is a safety device that prevents an inadvertent shift out of PARK when the engine is running. The driver must press the brake pedal before moving the shift lever out of the PARK position. The system consists of the following components:

With the ignition ON, battery voltage is supplied to the automatic transmission shift lock control switch. When the brake pedal is pressed, the contacts in the automatic transmission shift lock control switch close, suppling battery voltage to the automatic transmission shift lock control solenoid. With the transmission in the PARK position, the contacts in the park/neutral position switch are closed, suppling a path to ground for the automatic transmission shift lock control solenoid. This energizes the automatic transmission shift lock control solenoid, releasing the mechanical lock, allowing the driver to move the shift lever out of the PARK position.

The brake to shift lamp is a light that reminds the driver to press the brake pedal before attempting to move the shift lever out of the PARK position. The system consists of the following components:

When the ignition in the ON position, battery voltage is supplied to the brake to shift lamp. The BCM grounds the brake to shift lamp when the ignition is ON and the transmission is in the PARK position. When the brake pedal is pressed, the BCM receives a battery positive voltage signal from the stop lamp switch. The BCM responds by removing the ground from the brake to shift lamp control circuit, turning OFF the brake to shift lamp. This informs the driver that the shift lever may be moved out of the PARK position. When the transmission is out of the PARK position the park/neutral position switch grounds the BCM park gear input and the system is disabled. The BCM will turn the brake to shift lamp back ON when the park/neutral position switch is returned to the PARK position.