GM Service Manual Online
For 1990-2009 cars only

Trip Mode Display

The driver information display module calculates and displays the following vehicle parameters:

    • Average Fuel Economy
    • Instant Fuel Economy
    • Trip Range
    • Fuel Used
    • Average Speed

Only one of the above parameters is displayed at a time.

The user may change the parameter displayed by depressing the MODE button on the display face.

The user may change the display units from English to Metric by pressing the E/M button on the display face.

The driver information display module performs error detection where possible (no serial data stream for 10 seconds or an open circuit in the fuel level sender). If the driver information display module is unable to calculate a value due to a missing speed signal, the driver information display module will display an E when any of the following functions are selected:

    • AVG ECON
    • INST ECON
    • AVG SPEED

In the absence of vehicle communications, the driver information display module will display a double dash - - in the digits section. The display format for each mode is indicated in the following table.

Driver Information Display Module Format

Parameter

Update Range

Range

Reset Value

Units

Instant Fuel Economy

1 second

0-99

--

MPG or L/100 km

Average Fuel Economy

2 seconds

0.0-99.9

0.0

MPG or L/100 km

Average Speed

2 seconds

0.0-999

0.0

MPH or km/h

Fuel Used

0.1 gallon/liter

0.0-999

0.0

G or L

Trip Range

8 seconds

40-999

LO<43

--

Miles or km

Reset Operation

In order to reset the driver information display module, press the following buttons simultaneously for at least 2 seconds:

    • The MODE button
    • The ENGLISH/METRIC button

The reset is acknowledged when the display shows all segments ON for about 1 second.

Only the following modes may be reset:

    • AVG ECON
    • FUEL USED
    • AVG SPEED

A reset will affect all 3 modes simultaneously.

Average Economy

The average fuel economy is calculated as the ratio between the accumulated distance and the accumulated fuel consumption since the last average fuel economy reset (Distance/Fuel Used). After a trip reset, the average fuel economy will zero out the accumulated distance and the accumulated fuel consumption. The driver information display module will retain the average fuel economy information when the ignition switch is in the OFF position.

Instant Fuel Economy

Instantaneous fuel economy is the ratio between the accumulated distance gathered for the last 1 second and the accumulated fuel used for the last 1 second. This mode may not be reset. The value is not retained when the ignition switch is in the OFF position.

Range

Range is calculated as the product of the average fuel economy multiplied by the amount of fuel remaining in the tank (average fuel economy x Remaining Fuel). When a range of less than 40 miles is calculated, the low fuel range mode is entered. During the low fuel range mode, the numeric display will show LO. A reset will not have any effect while in range mode. If the average fuel economy is reset, range will not be affected until about 3 hours of new average fuel economy data is obtained.

Fuel Used

The driver information display module calculates and displays the total amount of fuel used since the last FUEL USED reset. Fuel used is the amount of fuel used since the last reset, accumulated from liters or fuel over real time converted to gallons or liters as required. Press the MODE and the ENGLISH/METRIC buttons simultaneously while in the FUEL USED display in order to reset the FUEL USED accumulator to zero. The value of the fuel is retained when the ignition switch is in the OFF position.

Average Speed

Average speed is the ratio of the accumulated distance over accumulated ignition on-time. Both values are calculated since the last average speed reset. On-time is measured from the time when the ignition switch is turned to the ON position to when the ignition switch is turned OFF of all of the ignition cycles since the last reset. Press the MODE and the ENGLISH/METRIC buttons simultaneously in order to reset the average speed to zero. The value of the average speed is retained when the ignition switch is in the OFF position.

Compass Display

With the long overhead console the compass display circuitry is entirely contained within the driver information display module. With the short overhead console the compass display circuitry is mounted externally, to the right of the driver information display module. Refer to Navigation Systems in order to initiate the compass self-calibration function or to set the variance.

Temperature Display

The driver information display module applies voltage to the ambient air temperature sensor. The ambient air temperature sensor is a thermistor.

As temperature increases, the resistance decreases.

As temperature decreases, the resistance increases.

As the resistance of the ambient air temperature sensor increases, the driver information display module senses a larger voltage reduction across the ambient air temperature sensor. This condition indicates a lower temperature.

As a resistance of the ambient air temperature sensor decreases, the driver information display module senses a smaller voltage reduction across the ambient air temperature sensor. This condition indicates a higher temperature.

If the temperature is below 3°C (38°F), the temperature digits will toggle between displaying the outside temperature and ICE for 2 minutes. This condition will occur once per ignition cycle.

The driver information display module uses the vehicle speed signal from the vehicle control module in order to determine when to update the temperature display with a new outside air temperature reading. The vehicle must be driven more than 16 km/h (10 mph) before the temperature display will be updated. For more information on temperature display operation, refer to Driver Information Center (DIC) or Message Center Description .

Dimming Control

Display dimming for the trip calculator will follow the radio dimming characteristics. When the park lamps are activated, the display will step dim to the maximum brightness in the dim mode. Further dimming will be controlled by the IP dimming control. The display will turn blank when the dimming control is moved to the lowest dimming request.