Fuel consumption, function - GF54.50-P-2007QA

MODEL 209.3 /4 with CODE (245) Trip computer 

Fuel consumption from "starting" (short distance memory), function 

Fig 1: Display Fuel Consumption (Short Distance Memory)

Courtesy of MERCEDES-BENZ USA

Fuel consumption from "reset" (long distance memory), function 

Fig 2: Display Fuel Consumption (Long Distance Memory)

Courtesy of MERCEDES-BENZ USA

The "as of starting" and "as of reset" for the travel time can be activated via the system selection buttons (S110s3) and scrolling forwards and backwards buttons (S110s1) of the multifunction steering wheel.

Depending on the unit setting (miles/kilometers) and the national variant coding of the instrument cluster (A1) the fuel consumption is displayed in:

• Miles per gallon
• Liters per 100 km
• Kilometers per liter (for code (498) Japanese version)

The trip computer determines the average fuel consumption, the travel distance covered and the consumption signal.

The consumption signal contains information about the quantity of fuel injected per unit time.

The instrument cluster (A1) receives the data as follows:

• The consumption signal is produced by the motor electronics control unit (N3/10) or by the CDI control unit (N3/9) and is placed as a message on the engine compartment CAN.
• The travel distance covered is determined from the 4 wheel RPM. The signals come from the ESP and BAS control unit (N47-5) via the engine compartment CAN.

  After resetting it can take up to 3 kilometers/miles or 2 minutes until sufficient data is available in order to calculate the consumption correctly and display it. During this time and depending on the adjustment (miles/kilometers) and coding of the national version of the instrument cluster (A1) 5.8 MPG, 40 l/100 km or 2.5 km/l are displayed.

If in the multifunction display (A1p13) "as of starting" (short distance memory) and in the multifunction display (A1p13) "as of reset" (long distance memory) different values are displayed, this is quite normal, as the two displays access different data records.

The "Since start" display (short-distance memory) reacts much more sensitively to the current driving situation than the "Since reset" display (long-distance memory).