Driver Information Center (DIC) Description and Operation: Odometer
WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
The instrument panel cluster (IPC) displays the vehicle odometer in the driver information center (DIC). The IPC calculates the vehicle odometer based on serial data vehicle speed information from the engine control module (ECM). The IPC stores the odometer information in non volatile memory and displays 'error' in the DIC if an internal IPC memory failure is detected. When the ignition is in RUN, the vehicle odometer is accessed through the trip/fuel DIC switch. When the ignition is OFF or ACCY and the trip/fuel switch is pressed, the DIC displays the odometer. The odometer displays miles or kilometers as selected from the DIC vehicle information switch.