Fuel Gauge

The fuel gage sending unit is mounted on the top surface of the fuel tank. The fuel level sender itself consists of a float that rides on the surface of the fuel in the tank, and a variable resistor 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 ground. The position of the gage pointer is determined by the strength of the current flowing through the gage.

If the tank is full. the resistance of the variable resistor is high (90 ohms) and the current flow through the gage is at a minimum. This causes the pointer to indicate the "F" mark on the gage dial.

If the fuel level is low, the resistance of the variable resistor is also low and current flow through the gage is high. This causes the pointer to show a low fuel level reading. intermediate fuel levels cause the pointer to indicate the corresponding position between "F" and "E".