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GF54.30-P-3022Q Displaying Distance, Function



GF54.30-P-3022Q Displaying Distance, Function

Estimation of mileage
To calculate the mileage and speed, the computer in the instrument cluster (A1) evaluates the wheel speeds of the following rpm sensors:
^ Left front rpm sensor (L6/1)
^ Right front rpm sensor (L6/2)
^ Left rear rpm sensor (L6/3)
^ Right rear rpm sensor (L6/4)

The instrument cluster (A1) receives the wheel speeds in rpm via the engine compartment CAN from the ESP and BAS control unit (N47-5).

Displaying the total mileage
The 6-digit display appears in kilometers or miles in the start screen below the multifunction display (A1p13) as soon as the instrument cluster (A1) is activated.
The range for the total mileage odometer is from 0 to 999999 kilometers or miles. If the maximum mileage is reached, the counter is not reset to "0".
The internal counter continues to operate up to a maximum of 1677721 kilometers or 1 000 000 miles. Processing is always performed in kilometers, the mileage display is a conversion. It is then necessary to replace the instrument cluster (A1).

Saving of mileage counts
The total mileage figure remains stored for at least 5 years, even if the voltage supply is disconnected. The trip mileage is also protected against data loss if the battery is removed for a short period of time. In normal operation, functional availability is guaranteed for the entire service life of the vehicle (15 years or 10 000 operating hours). Each timer changeover of the lowest value is continually stored and protected against loss.

Displaying the trip mileage
The trip mileage is displayed as a 5-figure number on the main screen of the multifunction display (A1p13) in kilometers or miles as soon as the instrument cluster (A1) is activated.

The range for the trip mileage odometer is from 0 to 9999.9 kilometers or miles. The display is reset to 0 once the maximum mileage is reached.

Resetting the trip mileage odometer
The trip mileage odometer is reset to "0" by pressing the instrument lighting rheostat and reset button (A1r1) for more than t = 2 seconds.

Requirements:
^ The instrument cluster (A1) must be activated.
^ The main screen (total and trip mileage) must be displayed on the multifunction display (A1p13).

Kilometers/miles switchover
The mileage display can be switched over from kilometers to miles by means of the "Settings" function.

The system responds to implausible CAN messages for all wheel speed signals by freezing the trip and overall odometer readings while simultaneously storing an error bit. The current reading on the total mileage odometer is also relayed on the interior CAN by the instrument cluster (A1).