Fuel Level Indication System

FUEL LEVEL INDICATION SYSTEM
The fuel level indication system is a magnetic-type indication system, which consists of:
1. Fuel pump module (located in the fuel tank).
2. Low fuel level warning switch (located on the back of instrument cluster).
3. Instrument cluster gauge amplifier (located on the back of instrument cluster) (Taurus).
4. Fuel gauge (located in the instrument cluster).

Fuel Gauge
1. The magnetic fuel gauge consists of three primary coils, one of which is wound at a 90-degree angle to the other two.
2. The coils form a magnetic field which varies in direction according to the variable resistance of the fuel pump module connected between two of them.
3. A primary magnet, to which a shaft and pointer are attached, rotates to align to this primary field, resulting in pointer position.
4. The bobbin/coil assembly is pressed into a metal housing which has two holes for dial mounting.
The fuel pump module changes resistance according to the level of fuel in the fuel tank, which varies the current flow through the gauge. The pointer position varies proportionately to the current flow.

CAUTION: Do not remove magnetic gauge pointers; the gauge cannot be recalibrated.

The pointer of the magnetic gauge remains in relatively the same position when the ignition is turned to OFF position.

There is no adjustment, calibration, or maintenance required for these fuel gauges.

Instrument Cluster Gauge Amplifier
The conventional instrument cluster contains an instrument cluster gauge amplifier.

The instrument cluster gauge amplifier provides a delay to the fuel gauge to prevent the fuel gauge pointer from fluctuating as a result of excessive movement in the fuel tank.

Low Fuel Level Warning

Low Fuel Level Warning Switch






The low fuel warning feature is available on vehicles with a conventional instrument cluster. These clusters will have the low fuel level warning switch, which:
1. Has additional circuitry to turn on a LOW FUEL warning indicator when the fuel gauge shows approximately one-eighth tank of fuel remaining.
2. Is not designed to proveout the LOW FUEL warning indicator; however the indicator may flash ON momentarily just after ignition switch is turned to RUN.
3. Is a small printed circuit board which latches into a pocket on the back of the instrument cluster.
The electrical connections for ignition, ground, input from fuel sender, output to fuel gauge, and Low Fuel warning output are made through a spring-type connector on the low fuel level warning switch to the flex circuit on the instrument cluster.

There are no provisions for calibration or adjustment of the low fuel level warning switch.

Fuel Pump Module
1. The fuel pump module assembly consists of a variable resistor controlled by the level of an attached float in the fuel tank.
2. When the fuel level is low, resistance in the fuel pump module is low and movement of the fuel gauge indicator dial is minimal (from EMPTY position).
3. When the fuel level is high, the resistance in the fuel pump module is high and gauge indicator dial movement is greater (further from the EMPTY position).