DOOR AJAR INDICATOR
DESCRIPTION
A door ajar indicator is standard equipment on all instrument clusters. This indicator is located within the odometer/trip odometer Vacuum Fluorescent Display (VFD) unit. However, on vehicles equipped with the optional Electronic Vehicle Information Center (EVIC) the door ajar indicator in the odometer VFD is electronically suppressed so as not to duplicate indications that are provided by the EVIC. The door ajar indicator consists of the text door, which appears in place of the odometer/trip odometer information in the odometer VFD unit.
The odometer VFD is soldered onto the cluster electronic circuit board, and is visible through a window with a smoked clear lens located on the lower edge of the tachometer gauge dial face of the cluster overlay. The dark lens over the VFD prevents it from being clearly visible when it is not illuminated. The door ajar indicator appears in the same blue-green color and at the same lighting level as the odometer/trip odometer information when it is illuminated by the instrument cluster electronic circuit board.
The door ajar indicator is serviced as a unit with the VFD in the instrument cluster.
OPERATION
The door ajar indicator gives an indication to the vehicle operator that one or more of the passenger compartment doors may be open or not completely latched. This indicator is controlled by the instrument cluster logic circuit based upon cluster programming and electronic messages received by the cluster from the Body Control Module (BCM) over the Programmable Communications Interface (PCI) data bus.
The door ajar indicator function of the Vacuum Fluorescent Display (VFD) 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 ignition switch output (run-start) circuit. Therefore, the VFD door ajar indication will always be OFF when the ignition switch is in any position except ON or START. The instrument cluster will turn ON the door ajar indicator for the following reasons:
- Door Ajar Indicator Lamp-On Message - Each time the cluster receives an electronic door ajar indicator lamp-ON message from the BCM indicating that a door is open or not completely latched, the door ajar indicator will be illuminated. If the ignition switch is in the ON position and the vehicle is not moving when the lamp-ON message is received, the VFD will repeatedly and sequentially cycle the door ajar indication in two second intervals with the odometer/trip odometer information and any other active warnings including: gate ajar and glass ajar. If the vehicle is moving, or once the cluster of a non-moving vehicle receives an electronic vehicle speed message from the Powertrain Control Module (PCM) indicating a speed greater than zero, the warning sequence will consist of three complete display cycles with an audible single chime tone accompanying each cycle, then revert to only the visual door ajar indication and odometer/trip odometer display cycling until the door ajar switch is cycled. The door ajar indicator will also be extinguished when the cluster receives a lamp-OFF message from the BCM, or if the ignition switch is turned to the OFF position, whichever occurs first. The VFD can be reverted to the odometer display and any currently displayed textual messages suspended by momentarily depressing and releasing the odometer/trip odometer reset switch button on the front of the cluster.
The BCM continually monitors the door ajar switches to determine the status of the doors. The BCM then sends the proper lamp-ON and lamp-OFF messages to the ElectroMechanical Instrument Cluster (EMIC).
For proper diagnosis of the door ajar switches and circuits, the BCM, the EMIC, the PCI data bus or the electronic communication related to door ajar indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.