Certain instrument panel cluster (IPC) features are tested when the ignition is turned on in order to verify that the features are working properly. The following indicators illuminate briefly at key up:

Refer to Indicator/Warning Message Description and Operation.

The engine control module (ECM) calculates the engine coolant temperature as determined by the coolant temperature sensor. The ECM sends the engine coolant temperature to the body control module (BCM) via the serial data circuit. The instrument panel cluster (IPC) displays the engine coolant temperature when the BCM sends a serial data message to the IPC indicating the engine coolant temperature. The engine coolant temperature gage defaults to 0° or below if:

The engine control module (ECM) sends the fuel level percent to the BCM via the serial data circuit. The IPC displays the fuel level as received from the BCM. The fuel gage defaults to E (empty) if:

When the fuel level is less than a pre-determined value, the Low Fuel indicator message illuminates.

The odometer shows how far the vehicle has been driven, in either miles (domestic) or kilometers (export). The odometer is shown on display when any of the following occur:

Odometer readings are displayed in the IPC based on serial data message from the BCM. The ECM calculates the distance traveled from the vehicle speed sensor (VSS) input. The BCM receives a serial data message from the PCM and stores the current mileage.

The IPC stores the last valid odometer reading from the BCM in non-volatile memory. When a new valid odometer reading is received from the BCM, the IPC will update the display and store the new reading.

The IPC also receives serial data messages from the BCM regarding VIN and Vehicle content information. Valid information is stored in non-volatile memory at the first key-up with a new IPC. If the VIN or option content do not match the stored information, the odometer will display ERROR.

The IPC displays the vehicle speed based on the information from the BCM. The ECM calculates the vehicle speed based on the vehicle speed sensor (VSS) input. The ECM sends a serial data message to the BCM indicating the vehicle speed. The BCM sends a serial data message to the IPC indicating the vehicle speed.

The speedometer defaults to 0 km/h (0 mph) when any of the following occur:

The IPC displays the engine speed as determined by the ECM. The ECM determines the engine speed and sends a serial data message to the BCM indicating the engine speed. The tachometer will default to 0 RPM if:

Trip odometer readings are calculated by the IPC based on the odometer reading received through a serial data message from the BCM. The trip odometer is shown when selected with the odometer trip reset stem. To reset the trip odometer, press and hold the trip reset stem for about two seconds, until the trip odometer shows zero.

The inside rear view mirror (ISRVM) uses two magnetic field sensors for compass direction. One sensor is for the north and south, the other is for east and west. The ISRVM provides a signal and a low reference to each sensor. As the vehicle travels with or against the earths magnetic pull, there is a change in voltage on one or both sensors. As a result of the change in voltage, the mirror changes the heading on the compass display. For the compass variance and calibration information refer to Compass Calibration and Magnetic Variance.