O/T 1990 Chevy K1500 not getting fuel, update

My plow truck has decided not to run! Turning the ignition on the fuel pump does not run. Going to the run position and holding it for awhile the fuel pump still does not run. Squirting starting fluid into the throttle body the truck starts and runs until the starting fluid is used up. Tested the fuel pump relay and the fuel pump relay socket as follows:

Just got done testing my fuel pump relay off of the truck using a multi-meter and a 9 volt battery. It works fine, so I think I have a problem in the wiring or some other sensor or switch. I tested the fuel pump connector with the key on and the key off with a power probe and got the following results,
Key Off socket A 12 v pos Socket C open, Socket F open, socket E ground, socket D Ground.
Key ON socket A 12 v pos, socket C open, socket F, E, D ground
socket diagram __ ____ __
F E D
___ ___
A C

Is it possible and okay to run power to the ADL , then start and run the plow truck that way. I know I'm passing the low or no oil pressure safety that way but need to have the truck running to plow with.

Also does anyone have any idea of what to check next, I'm about of ideas.

Thanks,
Bill

A few ideas that I have:
Bad connector at the fuel pump. May not be making full contact with pump terminal

Bad connector in the harness between fuel pump relay and fuel pump. Possible corrosion in a connector causing a loss of contact.

Wire going to fuel pump rubbed through on chassis. These harnesses do go through some places where they can rub and not be seen.

Tank or pump grounding. You need a ground to complete the circuit. Getting power to the pump is only half of the battle. Make sure that the pump is properly grounded.

I suggest some checking and tracing of wiring. Start at the fuel pump relay. See that it is getting voltage where it should be getting voltage. Next, see if it is truly being energized and passing power into the pump circuit.

If all else fails, and you need the truck, you may want to think about calling in an expert. It may cost a bit in the short run, but will pay you in the long run.

Please note. If I put power to the ADL test port for the pump the pump runs fine. Relay was benched and works fine. I need to know if I can run the truck okay with applying power to the ADL test port with the key on. In the test it is applied with the key off. I think the missing part seeing as terminal "A" always has 12 volts is the missing ground to socket "C"

(quoted from post at 09:15:49 02/04/19) Please note. If I put power to the ADL test port for the pump the pump runs fine. Relay was benched and works fine. I need to know if I can run the truck okay with applying power to the ADL test port with the key on. In the test it is applied with the key off. I think the missing part seeing as terminal "A" always has 12 volts is the missing ground to socket "C"

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"C" is NOT supposed to be grounded, it's the lead to the ALDL test terminal.

"F" needs to be grounded, and "D" gets power from the 'puter when it wants the fuelpump to run.



If you are testing for voltage with the ignition "ON", the "D" terminal will only have power for a few seconds for "priming", then the 'puter times out and it won't have power again 'til the engine is cranked or you recycle the key.

For now, there's no reason you can't jumper fused power to the "C" terminal and get your snow plowed.

My parents had a 90 suburban fuel pump went out 1/2 tank of fuel, no warning one min running next not.

THANK YOU TO EVERYONE WHO RESPONDED. I ENDED UP REMOVING THE RELAY, JUMPING FROM THE E PORT ON THE SOCKET TO A SWITCH THEN TO A CIRCUIT BREAKER THAN TO THE POSITIVE POST OF THE BATTERY. i TEMPORARILY RNA THE TWO WIRES UNDER THE BACK OF THE HOOD TO THE PASSENGER SIDE WINDOW AND INTO THE TRUCK WHERE i PLACED THE SWITCH ON THE SEAT. TESTED AND IT WORKS GREAT! i MAY EXTEND THE WIRES INSIDE THE CAB SO THAT THE SWITCH IS CLOSER TO ME WHEN I'M DRIVING. WHEN THE WEATHER GETS WARMER I'LL TRY TROUBLE SHOOTING THE CIRCUITS MORE. IF I CAN LOCATE THE PROBLEM I'LL MAKE A MORE PERMANENT SOLUTION COMING OF A HOT IN RUN AND START CIRCUIT IN THE FUSE BLOCK TO A SWITCH IN THE DASH, OR DIRECTLY THE PUMP CIRCUIT.

(quoted from post at 15:48:17 02/04/19) THANK YOU TO EVERYONE WHO RESPONDED. I ENDED UP REMOVING THE RELAY, JUMPING FROM THE E PORT ON THE SOCKET TO A SWITCH THEN TO A CIRCUIT BREAKER THAN TO THE POSITIVE POST OF THE BATTERY. i TEMPORARILY RNA THE TWO WIRES UNDER THE BACK OF THE HOOD TO THE PASSENGER SIDE WINDOW AND INTO THE TRUCK WHERE i PLACED THE SWITCH ON THE SEAT. TESTED AND IT WORKS GREAT! i MAY EXTEND THE WIRES INSIDE THE CAB SO THAT THE SWITCH IS CLOSER TO ME WHEN I'M DRIVING. WHEN THE WEATHER GETS WARMER I'LL TRY TROUBLE SHOOTING THE CIRCUITS MORE. IF I CAN LOCATE THE PROBLEM I'LL MAKE A MORE PERMANENT SOLUTION COMING OF A HOT IN RUN AND START CIRCUIT IN THE FUSE BLOCK TO A SWITCH IN THE DASH, OR DIRECTLY THE PUMP CIRCUIT.

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I'm curious, wouldn't it operate with the jumper wire to the ALDL port?

Must NOT have, for all the effort you put into your temporary setup!