Fuel Distance/Mileage Module: Description and Operation

Description
The Message Center Control Assembly Switch Module (MCCA) is only available on vehicles equipped with an electronic instrument cluster (EIC).

The message center receives signals from the Vehicle Speed Sensor (VSS), fuel tank sending unit, outside air temperature sensor, and the Powertrain Control Module (PCM).

The message center goes through a prove out when the ignition switch is turned to the ON position. The message center then resumes the mode of operation last used.





Directly below the message center is the message center control assembly (MCCA) switch module. The MCCA includes the following controls:
- SELECT
- RESET
- ENG/MET
- TRIP/RST
- OD/TRIP

Operation

SELECT
The SELECT button moves the message center cursor to the desired display.

ENG/MET
The ENG/MET button switches the electronic instrument cluster (EIC) displays to read in either English or metric measurement. Upon starting the vehicle, the EIC will return to the units displayed before shut off.

RESET
The RESET button will return the average fuel economy display (AVG ECONOMY) to zero.

TRIP/RST
The TRIP/RST button will clear the trip distance displayed on either the TRIP 1 or TRIP 2 displays.

OD/TRIP
The OD/TRIP button will switch the odometer display between TRIP 1, TRIP 2, and odometer.





Message Center/Fuel Computer Displays
The message center displays are:
- OUTSIDE TEMP (outside temperature)
- INST ECONOMY (instantaneous fuel economy)
- AVG ECONOMY (average fuel economy)
- TO EMPTY (distance to empty)

Instantaneous Fuel Economy
The INST ECONOMY is the fuel economy calculated at that instant. The range of instantaneous fuel economy can be displayed from 99-0.0 liters/100km (0.00-99.9 miles/gal).

Average Fuel Economy
The AVG ECONOMY is the fuel economy obtained since the average fuel economy display was last reset. The range of average fuel economy can be displayed from 99-0.0 liters/100km (0.00-99.9 miles/gal). The average fuel economy is reset by pressing the RESET button.

Distance to Empty
The TO EMPTY is the distance the vehicle can be driven before the fuel tank is empty. The range of distance to empty can be displayed from 0-999 kilometers or miles.

NOTE: Distance to empty cannot be reset.

Outside Temperature
The OUTSIDE TEMP is a feature which displays the temperature of the air outside of the vehicle.
The computer in the electronic instrument cluster (EIC) is designed to prevent inaccurate temperature displays due to the effects of engine heat on the sensor at slow speeds. In circumstances where the vehicle experiences an abrupt temperature rise, such as driving out of a cool garage on a warm day, the outside temperature display may show readings which are lower than expected. This condition will be corrected after the vehicle is driven at speeds of 50 km/h (30 mph) or greater for a period of time that is dependant upon the temperature difference experienced.