Odometer - Operation

OPERATION

The odometer gives 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 Controller Area Network (CAN) data bus.

The odometer information is displayed by the instrument cluster fixed segment Organic Light Emitting Diode (OLED) display. The OLED will display the odometer information whenever either front door is opened with the ignition switch in the OFF or ACCESSORY positions. The instrument cluster circuitry controls the OLED and provides the following features:

- Communication Error - If the cluster fails to receive an electronic distance message during normal operation, it will hold and display the last data received until the ignition switch is turned to the OFF position. 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 value stored in the cluster memory. If the cluster is unable to display odometer information due to an error internal to the cluster, the OLED will display dashes - - - -.
- Self Test - Each time the cluster is put through the self test, the odometer OLED will display all of its segments simultaneously during the OLED portion of the test to confirm the functionality of the OLED and the cluster control circuitry.

The PCM continually monitors the vehicle speed pulse information received from the wheel speed sensors, then sends the proper messages to the instrument cluster, also known as the Cab Compartment Node (CCN).

For proper diagnosis of the wheel speed sensors, the PCM, the CCN, the CAN data bus or the electronic communication related to odometer operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.