Brake Transmission Shift Interlock Solenoid

The BTSI solenoid is energized by the BCM switching BTSI control circuit (Tan/Black wire) to ground. When energized, the BTSI solenoid will allow shifting from Park. A condition for shifting from Park is that the brakes must be applied. The BCM receives this information over the serial data line from the PCM. The BCM also monitors the ignition circuit (Light Green wire) and ignition circuit (Yellow wire) to determine if the ignition switch is in the RUN or the ACC position. See WIRING DIAGRAMS  .