is wired into fuel pump ground circuit. With low speed fuel pump relay contacts in normally closed position,
there is no extra resistance in ground circuit, allowing high speed operation. For low speed fuel pump operation,
PCM will ground Low Fuel Pump (LFP) circuit, which opens relay contacts, causing fuel pump ground circuit
to pass through a resistor. See Fig. 29 . For additional fuel pump information, see FUEL DELIVERY under
FUEL SYSTEMS (GASOLINE).
2003 Ford Pickup F150
2003 ENGINE PERFORMANCE Theory & Operation - CNG, Flex-Fuel & Gasoline