Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

The body control module (BCM) calculates the mileage based on the vehicle speed signal circuit from the engine control module (ECM). The BCM then sends a serial data message to the instrument panel cluster (IPC) indicating the value of the odometer. The odometer will display 'error' if an internal BCM memory failure is detected. The odometer displays either miles or kilometers and the desired units can be accessed by pressing the trip/reset switch.

Schematic Reference

Instrument Cluster Schematics

Connector End View Reference

Instrument Panel, Gages, and Console Connector End Views

Electrical Information Reference

Scan Tool Reference

Scan Tool Data List

1. Ignition OFF, disconnect the DIC switch connector.
2. Test for less than 1 ohm of resistance between the DIC switch ground circuit and ground.

⇒	If greater than 1 ohm, test the ground circuit for an open/high resistance.

3. Ignition ON, verify the scan tool Trip Reset Switch parameter is Inactive.

⇒	If not inactive, test the signal circuit for a short to ground. If the circuit tests normal, replace the IPC.

4. Install a 3-Amp fused jumper wire between the signal circuit and ground. Verify the scan tool Trip Reset Switch parameter is Active.

⇒	If not active, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the IPC.

5. If all circuits test normal, test or replace the DIC switch.

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.