CRUISE INDICATOR
DESCRIPTION
A cruise indicator is standard equipment on all instrument clusters. However, on vehicles not equipped with the optional speed control system, this indicator is electronically disabled. This indicator is located within the odometer/trip odometer Vacuum Fluorescent Display (VFD) unit.
The cruise indicator consists of the text CRUISE in the lower portion of the odometer VFD unit. The odometer VFD is soldered onto the instrument 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 cruise indicator appears in a 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 cruise indicator is serviced as a unit with the VFD in the instrument cluster.
OPERATION
The cruise indicator gives an indication to the vehicle operator when the speed control system is ON, regardless of whether the speed control is engaged. This indicator is controlled by the instrument cluster circuit board based upon cluster programming and electronic messages received by the cluster from the Powertrain Control Module (PCM) over the Programmable Communications Interface (PCI) data bus.
The cruise indicator 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 indicator will always be OFF when the ignition switch is in any position except ON or START. The indicator only illuminates when it is energized by the instrument cluster logic circuit. The instrument cluster will turn ON the cruise indicator for the following reasons:
- Cruise Indicator Lamp-On Message - Each time the cluster receives an electronic cruise indicator lamp-ON message from the PCM indicating the speed control system is ON, the cruise indicator is illuminated. The indicator remains illuminated until the cluster receives a lamp-OFF message from the PCM, or until the ignition switch is turned to the OFF position, whichever occurs first.
- Actuator Test - Each time the cluster is put through the actuator test, the cruise indicator will be turned ON, then OFF again during the VFD portion of the test in order to confirm the functionality of the VFD and the cluster control circuitry.
The PCM continually monitors the speed control switches to determine the appropriate outputs to the speed control servo. The PCM then sends the proper lamp-ON and lamp-OFF messages to the ElectroMechanical Instrument Cluster (EMIC).
For proper diagnosis of the speed control system, the PCM, the EMIC, the PCI data bus, or the electronic communication related to cruise indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.