What clicks? your short incomplete sentences aren't helping ya here.

I incorrectly assumed subfords diagrams where the same obd1 diagrams I was looking at here on my desk, missed that "F150" there for OBD II aspect in your OP.

OBD II or OBD I either way the system is the same works the same, only real difference is no can not ground fpr via diagnostic test port.

The circuits are the same colors even.

Doesn't matter if the the power makes it to the fuel pump relay on both circuits, if the computer doesn't or can't provide the ground for the relay to pull it in the pumps, neither one of them, can or will run. There will be no power to them beyond the FPR itself.

If you believe the fuel pump relay is closing then the computer and its fuel pump ground circuit is likely good the problem lies elsewhere, but its gonna be very hard to tell by "feel" with two relays working in unison next to each other.

If have doubts/and just not sure? then same test applies, find the lt blu- org wire running between the fuel pump relay socket and the PCM harness connector (looks like pin 80? but image isn't real clear) and ground it out. Then turn the key to "run" test both pumps via tank selector switch, if one or both pumps run? the problem is either the computer or its connection with the fuel pump relay socket.

If no joy manually providing ground for fpr? problem lies elsewhere but have eliminated that aspect of the system.

 

Good morning guys. As I said yesterday . I took off relay #2 at (fuse distr. box fender) tested for power. There is power (11 v) I turn key. No power. Did the same procedure with the relay in . Heard it click. No result.

 

How do I check the computer ???

 

Thanks danr1.

 

I will ask again:
Does the fuel pump relay make (close) when you turn on the key and drop back out (open) ones second later each time you turn on the key?

 

When I turn key on , it click. When I turn key off It does not click.

 

Have you checked or replace fuse #16 in the engine compartment fuse relay box?

 

Partially answers his question, what he wants you to do is feel for the fuel relay clicking when you turn the key to run and then feel if it clicks again a second or so later before turning off the key.

if so that would show the computer has connection with and is controlling the fpr.

With both PCM and FP relays clicking when turning the key to "run" it'll be hard to tell if both are actually getting pulled in by "feel", but would be easy to determine that secondary click, the computer timing out turning off the fuel after no start condition.

If working right you'd feel that click shortly after turning the key on but before shutting the key back off.

You have checked and replaced any and all blown fuses long before this point correct??

 

Ok, will do. I did check all the fuses at engine compartment , they all had power. None were bad.

 

Correct. Only one fuse seem to be bad. And I replace it, I will again check relay ( fuel relay) . And Will update you. Thanks

 

Hi guys, i have been testing the systems. I have power up to the selector switch. I notice that when i switch (selection) for pumps. front or rear at the rear of the switch i do not have any power. i doing this at the rear of the switch. Should i have power thru the switch when i selected rear or front pumps. How do i test the switch?

 

Let me be clear. I have power up to the selection switch. I flick selection for rear or front tanks. no power at that connection.??

 

If you have power with a loading test light at the selector switch and none out the the switch is bad and you need to replace it.


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Thanks Subford, went thru the whole testing process. Step by step as you guys lead me. Success !!! Selector switch ! Bad! After 11days vehicle down , at last sucess!! Replace the switch. Your guys are the best. Flying is not as hard As this troubleshooting a ford, but she is my baby - Thanks!!!

 

Your very welcome and yes Flying is not hard at all but it has been a few years since I have had my hands on the controls of a plane.
I do have a multi engine commercial instrument rated license.