Shift Interlock: Description and Operation

CIRCUIT OPERATION
The Transmission Position Switch receives Ignition voltage from I/P Fuse 6 in "RUN," "BULB TEST" and "START." When the Transmission Shift Lever is in "PARK," the switch relays voltage to the Brake Transmission Shift Interlock/Stop Light Switch Assembly. The Brake Transmission Shift Interlock Switch is normally closed, providing voltage to the Shift Inhibit Solenoid and "BRAKE TO SHIFT" Indicator, which are permanently grounded at G201. When the Shift Inhibit Solenoid receives voltage, it is energized and prevents the Transmission Shift Lever from being moved out of "PARK." When the brake pedal is depressed, the Brake Transmission Shift Interlock Switch opens, removing voltage from the Shift Inhibit Solenoid. This de-energizes the Solenoid, allowing operation of the Shift Lever.