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GF54.30-P-3018T Display Fuel Quantity, Function



GF54.30-P-3018T Display Fuel Quantity, Function


Component Identification:






Function
The fuel level and reserve gage (A1p2) is a 39-segment LCD bar graph indicator. The fuel level and reserve gage (A1p2) is switched on and off by the instrument cluster (A1).
The display readings are shown immediately after "Terminal 15 ON"; the display run-up is dampened, but the run-down is not. A hysteresis is implemented to prevent segment jittering of readings near the segment limits.

Fuel level gage sensor
The left fuel level sensor (B4/1) and right fuel level sensor (B4/2) measure the fuel level. The instrument cluster (A1) registers this percentage from the interior compartment CAN and uses this information as the basis for controlling the fuel level and low fuel display (A1p2) as well as the low fuel warning lamp (A1e4) as required.

Fuel level display
If the EIS [EZS] control unit (N73) is in the "Circuit 15 ON" position, the current tank capacity is displayed in the fuel level and reserve indicator (A1p2).
During refueling when the EIS [EZS] control unit (N73) is in position "circuit 15 ON", refueling is only detected (updating of the display) as of a replenishment quantity of at least 9 l. Once "circuit 15 ON" is switched on again the display is updated. There is always a delay before the display is updated. This inhibits fluctuations in the display, e.g. due to cornering.

Reserve range
If the reserve range (approx. 9 l) has been reached, the fuel reserve warning lamp (A1e4) lights up yellow when the engine is running.
The lamp is triggered with a delay period to prevent the lamp flickering.

The system responds to malfunctions by moving the needle in the fuel level and reserve gage (A1p2) to "0". The fuel reserve warning lamp (A1e4) does not come on.


Component Identification:






Function requirements:
"Circuit 15 ON"
In vehicles with "gas version" other functions can be operated and additional information can be display on the instrument cluster (A1).
Data is exchanged between the ME-SFI [ME] control unit (N3/10) and the instrument cluster (A1) via CAN-C (engine compartment CAN).

CNG (compressed natural gas) tank fill level display
The "CNG tank fill level display" multifunction display can be accessed by pressing the system selection button (S110s3) in the base function.

The "CNG tank fill level display" multifunction display can be selected as soon as "circuit 15R ON" but a real fuel gauge is only displayed with "circuit 15 ON" and the driver can then choose between the gas and petrol operating mode.