BCM Inputs and Outputs

^ Key In Ignition Switch Input: The BCM interfaces with the ignition key alarm switch. The ignition key alarm switch grounds circuit 80 when the key is fully inserted in the ignition switch. The switch opens when the key is removed from the ignition switch. The BCM uses the input or the operation of the key in ignition reminder. The ignition key alarm switch receives ground through circuit 1550.
^ Driver's Door Ajar Switch Input: The BCM uses the input for the operation of the key in ignition reminder and the headlamps ON reminder. The door lock switch grounds circuit 159 when the driver's door is open.
^ Driver Seat Belt Switch Input: The BCM determines when the driver's seat belt is fastened through the seat belt switch. The seat belt switch opens when the driver's seat belt is fastened. The seat belt switch closes when the driver's seat belt is unfastened, causing the switch to ground circuit 238. The BCM uses the input for the operation of the fasten belts lamp indicator and the chime reminder.
^ Left/Right Turn Signal Input: The BCM determines that the turn signal switch is ON when it senses a transition from an open to 8+ in either circuit 14 (left) or circuit 15 (right). The BCM determines that the turn signal is OFF when it senses a constant open or 8+ in either circuit 14 (left) or circuit 15 (right). The BCM uses the input for the operation of the turn signal reminder.
^ Vehicle Speed Input: The BCM determines the vehicle traveled distance when it interfaces with the vehicle speed circuit 389. The circuit grounds 4000 times per 1.6 km (1 mile) traveled. The BCM uses the input for the operation of the turn signal reminder.
^ Auxiliary Chime Input: The Driver Information Display (DID) interfaces with the BCM in order to chime when a vehicle door is open. The DID grounds the auxiliary chime input (circuit 653) for the period of time that the door remains open. The BCM sounds the chime 4 times when circuit 653 is grounded for more than 450 ms. The trip calculator interfaces with the BCM in order to sound the chime when the trip calculator displays a warning message. The trip calculator grounds the auxiliary chime input (circuit 653) for less than 450 ms, causing the BCM to sound the chime 1 time.
^ Park Lights OFF Input: The BCM senses a voltage signal through the park lights OFF input (circuit 1872) when the headlamp switch is in the OFF position. The circuit opens when the headlamp switch is in the PARK position or the HEAD position. The BCM uses the input for the operation of the headlamps ON reminder.
^ Fasten Belt Indicator Control Output: The BCM uses the fasten belt indicator control output for the operation of the fasten belts indicator. The BCM applies voltage to circuit 529. The application of voltage turns ON the fasten belt indicator. The fasten belts indicator is always grounded through circuit 1450.