Section 85 (Instrument Cluster): Odometer: Operation

WARNING: This page is about a different car, the 2004 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.

The odometer and trip odometer give an indication to the vehicle operator of the distance the vehicle has traveled. This indicator is controlled by the instrument cluster circuitry based upon cluster programming and electronic messages received by the cluster from the Powertrain Control Module (PCM) over the Programmable Communications Interface (PCM) data bus. The odometer and trip odometer information is displayed by the instrument cluster Vacuum Fluorescent Display (VFD). The VFD will the last previously selected odometer or trip odometer when the ignition switch is turned to the On or Start positions. The instrument cluster circuitry controls the VFD and provides the following features:

Odometer/Trip Odometer Display Toggling -Actuating the trip odometer reset switch button momentarily with the VFD illuminated will toggle the display between the odometer and trip odometer information. Each time the VFD is illuminated with the ignition switch in the On or Start positions, the display will automatically return to the last mode previously selected (odometer or trip odometer).
Trip Odometer Reset - When the trip odometer reset switch button is pressed and held for longer than about two seconds with the ignition switch in the On or Start positions, the trip odometer will be reset to 0.0 kilometers (miles). The VFD must be displaying the trip odometer information in order for the trip odometer information to be reset.
Communication Error - If the cluster fails to receive a distance message during normal operation, it will flash the odometer/trip odometer distance information on and off repeatedly until a distance message is received, or until the ignition switch is turned to the Off position, whichever occurs first. If the cluster does not receive a distance message within one second after the ignition switch is turned to the On position, it will display the last distance message stored in the cluster memory. If the cluster is unable to display distance information due to an error internal to the cluster, the VFD display will be blank.
Actuator Test - Each time the cluster is put through the actuator test, the odometer VFD will display all of its segments simultaneously, then step through each character segment individually during the VFD portion of the test to confirm the functionality of the VFD and the cluster control circuitry.

The PCM continually monitors the vehicle speed pulse information received from the vehicle speed sensor, then sends the proper distance messages to the instrument cluster. For further diagnosis of the odometer/trip odometer or the instrument cluster circuitry that controls these functions, (Refer to DIAGNOSIS AND TESTING - INSTRUMENT CLUSTER ). For proper diagnosis of the vehicle speed sensor, the PCM, the PCI data bus or the electronic message inputs to the instrument cluster that control the odometer/trip odometer, a DRBIII(R) scan tool is required. Refer to ELECTRONIC CONTROL MODULES .