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The fuel pumps are controlled by the fuel injection computer through the fuel pump relay. The computer will run the pump for 2 seconds each time the key is cycled from "off" to "run". It will then shut the pump off by opening the relay coil circuit. So don't expect to hear the pump running except during this two second interval. The computer will not restart the pump until it sees "PIP" pulses coming from the ignition module (either during crank or once the engine starts). No PIP, no fuel pump. You can force the fuel pump to run by grounding the "FP" wire in the diagnostic connector. Now, you may be way ahead of me and already know all this. Ground the FP wire to engage the fuel pump relay, then trace the output of the FP relay. Is it 12 volts or not? If not, deal with the relay or the power supply to same. If so, trace the 12 volts through the switch on the dash, and see why voltage does not reach the pump. There is a good website with how-to-fix forums for Ford trucks available at the link below
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