Fuel Tank Selector Switch: Description and Operation
OPERATIONVoltage is supplied to the Fuel Tank Selector Switch whenever the Fuel Pump relay is energized (contacts closed).
When the Fuel Tank Selector Switch is placed in the "FRONT" position, power is supplied from the 786 (R) terminal of the switch to the Front Tank Fuel Pump Motor. Fuel is then pumped from the front tank.
The signal from the Front Tank Fuel Gauge Sender is carried through the 673 (DB/Y) wire to the Fuel Tank Selector Switch, and then through the 29 (Y/W) wire to the Fuel Gauge in the instrument cluster.
When the Fuel Tank Selector Switch is in the "REAR" position, power is supplied to the Rear Tank Fuel Pump Motor through the 789 (BR/Y) wire from the Fuel Tank Selector Switch.
The Rear Tank Fuel Gauge Sender signal is transmitted to the Switch through the 675 (Y/LB) wire, and then to the instrument cluster through the 29 (Y/W) wire.