Fuel pumps stopped working out of no where.

[CDW]

I replaced the relay under the hood a while back and it ran fine drove it all day today. I went outside to move it and it ran then shut off the pumps where not working agian so i checked the relays.

The one by the computer brown and black parts number e3uf-12a645-b1a I have not replaced and i have no idea what the relay controlls the truck with start and run if you pump the pedal the hole time but its not priming with the pumps. It has new tank and sending unit and inline pump regulater replaced and fuel relay by the battery replaced

 

[RonD]

Relay with Brown base is the EEC relay it closes when key is turned on
It powers the computer(EEC), fuel injector, and spark system
Green base is Fuel pump relay
Black base is WOT(wide open throttle) relay, it turns off AC when extra power is needed.

There is a Fusible link that runs from starter relay to Fuel Pump Relay, that is the power for the fuel pump.
From fuel pump relay power runs to Inertia Switch in the passenger foot well, under glove box.
Inertia switch will cut fuel pump power if truck is in a crash, but they can just fail, there is a reset button on the top of the inertia switch.
From the inertia switch power runs to a Splice near the fuel pump in the frame rail.
This splice is where Ford tapped in to the power wire for the in tank pump, to power the frame rail pump.
Splice can often get corroded and fail.

Just FYI, the fuel pump only gets power for 2 seconds, when key is turned on, fuel pumps won't start again until engine starts or if you turn off the key and turn it on again.

 

[CDW]

Relay with Brown base is the EEC relay it closes when key is turned on
It powers the computer(EEC), fuel injector, and spark system
Green base is Fuel pump relay
Black base is WOT(wide open throttle) relay, it turns off AC when extra power is needed.

There is a Fusible link that runs from starter relay to Fuel Pump Relay, that is the power for the fuel pump.
From fuel pump relay power runs to Inertia Switch in the passenger foot well, under glove box.
Inertia switch will cut fuel pump power if truck is in a crash, but they can just fail, there is a reset button on the top of the inertia switch.
From the inertia switch power runs to a Splice near the fuel pump in the frame rail.
This splice is where Ford tapped in to the power wire for the in tank pump, to power the frame rail pump.
Splice can often get corroded and fail.

Just FYI, the fuel pump only gets power for 2 seconds, when key is turned on, fuel pumps won't start again until engine starts or if you turn off the key and turn it on again.

I dont know where the problem was so I just stright wired the pumps for now.