Century V6-3100 3.1L VIN M SFI (1998)
Audible Warning Device: Component Tests and General Diagnostics
BCM Inputs and Outputs
KEY IN IGNITION SWITCH INPUT
The Body Control Module (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 key is removed from the ignition switch. The BCM uses this input for the operation of
the key in ignition reminder, lockout prevention, exit lighting, among other BCM-related features. The ignition key alarm switch receives ground
through circuit 1550.
DRIVER'S DOOR AJAR SWITCH INPUT
The BCM uses this input for the operation of the key in ignition reminder and headlamps on reminder. When the driver's door is open, the door
lock switch grounds circuit 49. Refer to Body Control Module (BCM) for more information regarding the driver's door lock ajar switch input.
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. When the driver's seat belt is unfastened, the seat belt switch closes. This causes the switch to ground circuit 238. The BCM uses this
input for the operation of the fasten belts indicator lamp and chime reminder.
PARK BRAKE INPUT
The BCM determines when the parking brake is applied through the park brake indicator switch. When the parking brake is released. the park
brake indicator switch opens. The park brake indicator switch closes when the parking brake is applied. This causes the switch to ground circuit
80. The BCM uses this input for the operation of the parking brake reminder.
PARK LAMP 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. This circuit
opens when the headlamp switch is in the PARK or HEAD position. The BCM uses this input for the operation of the headlamps on reminder.
CLASS II SERIAL DATA LINK
The BCM determines when the turn signal switch is on, and the vehicle traveled distance via the Class II serial data link. The BCM uses this
information to activate the turn signal reminder.
The BCM determines when the transaxle is shifted out of PARK via the Class II serial data link. The BCM uses this information to activate the
parking brake reminder
The Instrument Panel Cluster (IPC) uses the Class II serial data link when requesting the BCM to sound the low fuel reminder.
The BCM uses the Class II serial data link when requesting the Instrument Panel Cluster (IPC) to turn on the Fasten Belts indicator lamp.
Refer to Body Control Module (BCM) for more information. See: Body and Frame/Body Control Systems/Body Control Module
