BTSI Circuit Description

When the ignition switch is in the ON position, fuse #15 supplies B+ to the BRAKE TO SHIFT indicator and fuse #2 supplies B+ to the stop lamp switch. The BRAKE TO SHIFT indicator is turned ON when the BCM grounds terminal C15 of connector C2.

When the brake pedal is pressed, the BCM receives a signal at terminal D11 of connector C2. The BCM responds by not grounding terminal C15 of connector C2, which turns OFF the BRAKE TO SHIFT indicator. This informs the driver that the brake transmission shift interlock is operational.

When the brake pedal is pressed, the stop lamp switch supplies B+ to the automatic transmission shift lock control solenoid. The automatic transmission shift lock control solenoid is grounded through terminal 7 of the transmission control selector switch. The automatic transmission shift lock control solenoid energizes allowing the operation of the transmission control lever.