Fuel Gauge

The fuel gage sending unit is mounted on the top surface of the fuel tank. The fuel level sender itself consists of the following two components:
^ A float that rides on the surface of the fuel in the tank
^ A variable resistor that is controlled by the float arm

When electric power is supplied to the fuel gage, current flows through the gage to the variable resistor and then to a ground. The position of the gage pointer is determined by the strength of the current that is flowing through the gage.

If the tank is full the following situations occur:
^ The resistance of the variable resistor is high (90 Ohm).
^ The current flow through the gage is minimum.
^ The pointer indicates that the gage reads full (F) on the gauge dial.

If the fuel level is low the following situations occur:
^ The resistance of the variable resistor is low.
^ The current flow through the gage is high.
^ The pointer indicates a low fuel level reading.

Intermediate fuel levels cause the pointer to indicate the corresponding position between F and E.