Caprice V8-265 4.3L VIN W MFI (1995)
Shift Interlock: Description and Operation
The Backup Lamp Transmission Position Sensor Switch receives Ignition voltage from I/P Fuse #12 in "RUN," "BULB TEST" and "START." When
the Transmission Shift Lever is in "PARK," the switch relays voltage to the Brake Transmission Shift Interlock (BTSI) Switch. The BTSI Switch is
normally closed, providing voltage to the BTSI Solenoid, which is permanently grounded at G200. When the BTSI 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 BTSI Switch opens,
removing voltage from the BTSI Solenoid. This de-energizes the Solenoid, allowing operation of the Shift Lever.
