I am from the US but now in Northern Alberta on a hunting trip. Truck is up in the back country and has quit. It has two factory gas tanks, I can't hear either of the fuel pumps will come on when you turn the switch on. The problem started as an intermitting fuel starvation issue. Truck would act like it ran out of gas then pick up and go again. Switched tanks back and forth but it got worse throughout the day and finally will not start at all. I have listened to both tanks when the ignition switch is turned on but can not hear the pump come on for either tank (switching the selected tank with the switch on the dash). We went through some bumpy terrain just before the problem started so I am thinking maybe a wire might have come loose or got broke somehow. I am asking for wiring schematic help so I can check for voltage in the correct place going to the fuel pumps. Both tanks are full of gas so for now dropping either tank is not an option.

 

What year? What engine?

 

1997 460 sorry

 

Here's some diagrams.



This one has the fuel pump circuit. You might want to check that inertia switch.

 

Thank you so much for your time and info.

 

Wiring schematic shows the wire going to the fuel pump as "PK/B". What color is that?
I can't see the wires for the forward tank but at the rear tank, I have 2 black wires, 1 yellow/green & 1 orange wire going towards the sending unit.


Does the fuel pump run continuos once the motor is running? Can I run a wire from the battery straight to the fuel pump at least long enough to get the truck back to town? If so, of the wires listed above, which wire should receive the 12V?

 

Pink with black stripe. However, the dual-tank 97 F250 doesn't use that color wire.

Check the inertia switch first. It can be tripped by hitting a very hard bump.

Here is the schematic:
https://www.dropbox.com/s/jtcxl6aerj...0Tank.pdf?dl=0

Check for power for 1-2 seconds at the inertia switch when the ignition switch is first turned to run. If you have no power at the input during that duration, then go back upstream towards the relay and beyond. If you do have that power at the output of the switch, then investigate the selector switch circuit.

Other than that 1-2 second priming cycle, the pump will not run until the PCM detects the engine has started via an accelerating crank signal.

 

To projectSHO89 and Franklin2,
Thank you so much for this info. We must have broke wires between the selector switch and the tank. We had power to the inertia switch, power to the selector switch in and out, but no power to the tanks. We could get access to the harness at the rear tank so we ran a straight wire from the battery to the brown/w wire near rear tank and that pump fired right up. The truck ran fine all the way out of the bush country to town. I really appreciate you taking the time and sharing your knowledge. You bailed us out of a really tough spot.

 

Nice job Dave.... you've really helped a lot of people on this site...kudos~!