Moving the ignition switch to the CRANK position sends a 12 V signal to the PCM Ignition Crank input. The PCM verifies that it has received a valid theft deterrent signal from the vehicle's Body Control Module and that the transmission is in the PARK or NEUTRAL position. The PCM then grounds the control circuit of the Start Enable Relay. When the Start Enable Relay is energized it completes the B+ voltage circuit to the starter solenoid S terminal.