Fuel Gauge

The Fuel Gauge is a vacuum fluorescent bar display which is controlled by a microprocessor within the cluster. The cluster reads an analog resistance signal from the Fuel Gauge Sender and converts this signal into a digital signal used by the bar graph display. The Fuel Gauge Sender is a variable resistor. Its resistance is approximately 1 ohm with an empty tank.
The pointer of the Fuel Gage is moved by the magnetic fields of two coils. The coils are at right angles to each other. Battery voltage is applied to the E coil, and the circuit divides at the opposite end of this coil. One path continues to ground through the coil. Another goes to ground through the variable resistor of the Fuel Level Sender.
When the tank is low. the resistance of the Fuel Level Sender is low. A large flow of current passes through the E coil and the Fuel Level Sender resistor. This pulls the pointer towards E on the Scale. When the tank is full, the Fuel Level Sender resistance is high. More current now flows though the F coil, moving the pointer to on scale.
With two coils operating the pointer, the Fuel gage is not affected by changes in the voltage of the system.