GM Service Manual Online
For 1990-2009 cars only

Driver Information Center (DIC) Description and Operation Radio

The radio displays driver information center (DIC) information when it first powers up. The uplevel radio shows the time and ambient air temperature on the first line of the display and DIC information on the second line of the display.

There are 3 DIC buttons on the radio.

    • ENTER
    • INFO
    • MENU

ENTER

The ENTER button is used in order to acknowledge a warning message, reset an option, or to select an option.

INFO

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

    • AV SPEED
    • ECON
    • FUEL RANGE
    • OIL LIFE
    • TRIP A
    • TRIP B

AV 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 period. Press and hold the ENTER button on the radio for one second in order to reset the average speed display.

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 instrument panel cluster (IPC) 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 period and can be changed between English units and Metric units. Press and hold the ENTER button on the radio switch for one second in order to reset the ECON display.

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 radio 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

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

TRIP A and TRIP B

The instrument panel cluster (IPC) contains a season odometer and a trip odometer. Momentarily press the trip/reset switch in order to toggle between the season odometer and the trip odometer. Press the trip/reset switch for greater than 2 seconds, while the trip odometer is displayed, in order to reset the trip odometer. The IPC displays the vehicle mileage and trip mileage as determined by the IPC. The IPC calculates the mileage based on the vehicle speed from the engine control module (ECM). The odometer will display 'error' if an internal IPC memory failure is detected.

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 engine control module (ECM) sends the oil life remaining percentage to the body control module (BCM) via the serial data circuit. The radio receives serial data messages from the BCM indicating the remaining oil life. The radio displays the current percentage of the GM Oil Life System as determined by the ECM. When the oil life remaining percentage drops below 10 percent, the radio 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 ENTER button for 5 seconds until the radio displays ACKNOWLEDGED.

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

Ambient Air Temperature

The body control module (BCM) reads the ambient air temperature sensor. The temperature sensor is a 2-wire negative temperature co-efficient thermistor. The BCM provides 5 volts to an internal input resistor that is connected to the ambient air temperature sensor. The ambient air temperature is displayed in the driver information center (DIC) located in the radio. The ambient air temperature information is transmitted by the BCM for display in the DIC via the serial data circuit. The BCM provides the ambient air temperature information in Celsius. The radio converts the temperature to Fahrenheit, if required.

Indicators and Warning Messages

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

Driver Information Center (DIC) Description and Operation IPC

The driver information center (DIC) displays important vehicle information. The DIC also displays the odometer and ambient air temperature. The DIC switches are hardwired to and read by the instrument panel cluster (IPC). The BCM is responsible for driving and processing the DIC display via the serial data circuit. The BCM is also responsible for reading the ambient air temperature and season odometer. The ambient air temperature and season odometer is transmitted to the IPC via the serial data circuit for display in the DIC. The ambient air temperature data is transmitted in degrees Celsius and the IPC is responsible for converting the ambient air temperature to Fahrenheit.

There are 2 DIC switches located on the steering wheel controls:

    • INFO
    • SET/RESET

The 2 DIC switches have a third embedded switch function. 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 SPEED
    •  FUEL ECON (MPG AVG)
    • COOLANT
    • FUEL RANGE
    • OIL LIFE
    • TRIP A
    • TRIP B
    • INSTANTANEOUS FUEL ECONOMY (INSTANTANEOUS MPG)
    • TIRE PRESSURE

AV 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 period. Press and hold the RESET/SELECT button of the DIC for one second in order to reset the average speed display.

FUEL ECON (MPG AVG)

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 instrument panel cluster (IPC) 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 period and can be changed between English units and Metric units. Press and hold the RESET/SELECT button of the DIC switch for one second in order to reset the ECON display.

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.

INSTANTANEOUS FUEL ECONOMY

Instantaneous fuel economy (IFE) is calculated based on distance and fuel used information. Distance represents the accumulated distance travelled for a predetermined amount of time and fuel used information is the accumulated fuel delivered for the same predetermined amount of time. The distance is calculated by the IPC using the vehicle speed information from the ECM. The IFE values are retained when the ignition is turned OFF and can be changed between Metric and English units. The IFE values cannot be reset.

COOLANT

The DIC receives a serial data message from the BCM requesting the display of the engine coolant temperature. The engine coolant temperature is sent to the BCM as determined by the engine control module (ECM) via a serial data message.

OIL LIFE

The engine control module (ECM) sends the oil life remaining percentage to the 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 ECM.

TRIP ODOMETER

The instrument panel cluster (IPC) contains a season odometer and a trip odometer. Momentarily press the INFO switch in order to toggle between the season odometer and the trip odometer. Press the RESET switch for greater than 2 seconds, while the trip odometer is displayed in the DIC in order to reset the trip odometer. The IPC displays the vehicle mileage and trip mileage as determined by the BCM. The BCM calculates the mileage based on the vehicle speed data from the engine control module (ECM). The odometer will display 'error' if an internal IPC memory failure is detected.

TIRE PRESSURE

The IPC displays the front and rear tire pressure data in the DIC. The DIC displays the pressure for each of the front or rear tires. When a tire with low air pressure is present, the DIC displays XXXX XXXX TIRE PRESSURE LOW. The IPC receives the tire pressure data from the tire pressure monitoring (TPM) system via the serial data circuit.

RESET/SELECT

The RESET/SELECT 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 RESET/SELECT.

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 engine control module (ECM) sends the oil life remaining percentage to the body control module (BCM) via the serial data circuit. 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 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. Refer to GM Oil Life System Resetting.

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

Ambient 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. The temperature sensor is a 2-wire negative temperature co-efficient thermistor. The BCM provides 5 volts to an internal input resistor that is connected to the ambient air temperature sensor.

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 it does not receive a valid odometer reading form the BCM. The last known good odometer value from the BCM is displayed by the IPC. ERROR is displayed in the DIC when the IPC receives an invalid odometer value.

Indicators and Warning Messages

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