Door Ajar Warning Indicator - Operation

OPERATION

The ajar indicators give an indication to the vehicle operator that one or more of the passenger compartment doors or the liftgate may be open or not completely latched. These indicators are controlled by the instrument cluster logic circuit based upon cluster programming and electronic ajar switch status messages received by the cluster from the Totally Integrated Power Module (TIPM) over the Controller Area Network (CAN) data bus.

The ajar indicator function of the odometer or Electronic Vehicle Information Center (EVIC) Vacuum Fluorescent Display (VFD) unit is completely controlled by the instrument cluster logic circuit, and that logic will only allow this indicator to operate when the instrument cluster receives a battery current input on the fused B(+) circuit. Therefore, the VFD ajar indications can occur regardless of the ignition switch position. The instrument cluster will turn ON the ajar indicator for the following reasons:

- Ajar Switch Message Input - Each time the ElectroMechanical Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN) receives an electronic door or liftgate ajar switch status message indicating that a door, the liftgate or any combination of these is open or not completely latched with the ignition switch in any position, the appropriate ajar indication will be illuminated. If the cluster detects a vehicle speed input greater than zero (kilometers or miles-per-hour) while the ignition switch is in the ON or START positions, the ajar indication will be accompanied by a single chime tone. When the ignition switch is in any position except ON or START, any and all ajar indications will time out after about five minutes.

The TIPM continually monitors the door and liftgate ajar switches to determine the status of the doors and liftgate. The TIPM then sends the proper ajar switch status messages to the EMIC. The door and liftgate ajar switches and their circuits may be diagnosed using conventional diagnostic tools and methods. Refer to the appropriate wiring information.