GM Service Manual Online
For 1990-2009 cars only

The driver information center (DIC) displays important vehicle information. The DIC is also used to display the vehicle odometer and outside air temperature when other important vehicle information is not being displayed. The DIC switches are hardwired to and read by the instrument panel cluster (IPC). Battery power is provided to the DIC switch via the instrument panel cluster (IPC) with the DIC switch signal circuit pulled up to battery voltage in the IPC. The battery positive voltage circuit is fused in the body control module (BCM). The BCM is responsible for driving and processing the DIC display through the serial data circuit. The BCM is responsible for reading the outside air temperature (OAT) and season odometer. The outside air temperature and season odometer is transmitted to the IPC over the serial data circuit for display in the DIC. The OAT data is transmitted in degrees Celsius and the cluster is responsible for converting the outside air temperature (OAT) to Fahrenheit.

There are 2 DIC buttons on the instrument panel cluster (IPC):

    • INFO
    • SET/RESET

The 2 DIC buttons however provide 3 switch functions. Pressing the INFO and SET/RESET button at the same time provides the MENU switch function.

INFO

The INFO button is used in order to navigate through the following driver information center (DIC) information modes:

    • AV VEHICLE SPEED
    • AV FUEL ECON
    • COOLANT TEMPERATURE
    • FUEL RANGE
    • OIL LIFE MONITOR
    • TRIP ODOMETER A
    • TRIP ODOMETER B

Other instrument panel cluster (IPC) information displayed in the DIC are Season odometer and Outside Air Temp.

AV VEHICLE SPEED

Average speed is calculated using the equation: Average Speed = Distance/Ignition On

    • Distance = The accumulated distance travelled since the last reset of this value
    • Ignition On = The accumulated ignition on time since the last reset of this value

Ignition on time is measured from the time that the ignition is turned ON to the time when the ignition is turned OFF. The value of this mode is retained during ignition OFF. Press and hold the SET/RESET button on the DIC for 1 second in order to reset the average speed display.

AV FUEL ECON

Average fuel economy is calculated using the equation: AFE = Distance/Fuel

    • Distance = The accumulated distance travelled since the last reset of this value
    • Fuel = The accumulated fuel consumption since the last reset of this value

The DIC receives a serial data message from the body control module (BCM) regarding fuel usage information. The value of this mode is retained during ignition OFF and can be changed between English units and metric units. Press and hold the SET/RESET button on the DIC switch for 1 second in order to reset the ECON display.

COOLANT TEMPERATURE

The DIC receives serial data messages from the BCM requesting the display of the coolant temperature. The coolant temperature is sent to the BCM as determined by the PCM/ECM via a serial data message.

FUEL RANGE

This message indicates the estimated distance that the vehicle can travel under the current fuel economy and fuel level conditions since the last reset of the value. Fuel Range is calculated using the equation: Fuel Range = Distance Sum/Fuel Sum.

    • Distance Sum = The accumulated distance travelled since the last reset of this value.
    • Fuel Sum = The accumulated fuel delivered since the last reset of this value

The DIC receives a serial data message from the BCM with fuel information. The value of this mode is retained during ignition OFF and can be changed between English units and metric units. The FUEL RANGE display cannot be reset.

OIL LIFE MONITOR

The PCM/ECM sends the oil life remaining percentage to the body control module (BCM) via a serial data message. The DIC receives a serial data message from the BCM indicating the remaining oil life. The DIC displays the current percentage of the GM Oil Life System as determined by the PCM/ECM.

TRIP ODOMETER A and TRIP ODOMETER B

The DIC displays vehicle trip odometer mileage based on the vehicle speed signal (VSS) from the body control module (BCM). The trip odometer displays accumulated km (mi) since the last reset of this value. The trip odometer is capable of displaying up to 999.9 km (999.9 mi). Trip odometer information is not retained when the battery is disconnected. Press and hold the INFO button on the DIC for 1 second in order to reset the trip odometer display.

SET/RESET

The SET/RESET button is used in order to acknowledge a warning message, reset an option, or to select an option. Press and hold for 0.25 seconds to perform SET/RESET.

MENU

The MENU button is used in order to navigate through the following personalization modes:

    • AUTO UNLK
    • DELAY LOCK
    • EXT LIGHTS
    • LANGUAGE
    • LIGHT FLASH
    • LOCK HORN
    • OIL-LIFE RESET
    • REMOTE START
    • SECURITY
    • UNITS
    • UNLOCK HORN

OIL-LIFE RESET

The powertrain control module (PCM)/engine control module (ECM) sends the oil life remaining percentage to the body control module (BCM) via a serial data message. The driver information center (DIC) receives a serial data message from the BCM indicating the remaining oil life. The DIC displays the current percentage of the GM Oil Life System as determined by the PCM/ECM. When the oil life remaining percentage drops below 10 percent, the DIC displays CHANGE ENGINE OIL. When the engine oil is changed, reset the engine oil life in order to clear the oil life remaining percentage display. Press and hold the SET/RESET button for 5 seconds until the DIC acknowledges.

For more information on the rest of the personalization modes, refer to the Owner's Manual.

Outside Air Temperature

The outside air temperature is read by the body control module (BCM) and transmitted over serial data to the instrument panel cluster (IPC) for display in the driver information center (DIC). The BCM provides the logic for reading the outside air temperature sensor. The BCM sends the temperature to the IPC in Celsius. The IPC is responsible for displaying the temperature and converting to Fahrenheit.

Odometer

The odometer information is stored in the body control module (BCM) and is transmitted to the instrument panel cluster (IPC) for display in the driver information center (DIC). The IPC stores a backup copy of the odometer value in case the IPC does not receive a valid odometer reading form the BCM. The last known good odometer value from the BCM is displayed by the IPC before ERROR is displayed in the DIC.

Indicators and Warning Messages

For more information on driver information center (DIC) warning messages, refer to Indicator/Warning Message Description and Operation.