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Should work as long as it is sharp. Did not know you had that or I would have given you better tests. Substitute any test for 12v to use the test light. Test lights are much better than meters for testing 12v because they requires some amps to light the bulb. Not a lot but a meter requires much less. There have been times that I have read 12v on a meter but the test light may not light or lights very dim.Sometimes you can find a fault because of how the bulb lights.
 

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Discussion Starter #63
Update time!

Alright so, I have ordered all of my new diagnostic equipment, and a quality crimping tool to ensure that I can repair this with a factory finish.

I did rerun my 12V tests with my test light (so much more convenient), and the fuel pump plug/relay plug tested good with 12V.

I also replaced part of the relay plugs ground wire, which was testing 17.50Kohm before. Now with the new ground wire in place I am getting 3.4ohm consistently, which is something. After testing other points along that ground and getting the same 3.4ohm reading, it looks like that resistance is somewhere after the new wire and the earth connection.

I will be attempting some of the voltage drop tests in the future, but I would much prefer to wait for my new toys before I head down that rabbit hole.

Hope everyone is having a great weekend!
 

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I assume you mean you plugged in the jumper and got 12 V or good light at the pump plug. Plug the pump back in a pierce the ground at the pump ground on the wire side Does the the light work?
 

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Discussion Starter #65
2nd update,

I ran a ground from the splice to neg terminal on the battery, I tested the ground and got 0ohm, however it would not run. I pierced the fuel pump plug ground wire on the wire side and got 0ohm on it. I also put the test light on the same pierce and the test light lit up and showed 11.8V.

I'm thinking my next step is to pull the pump, bench test, and confirm operation in a closed loop where I control all of the parameters?
 

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I am pretty sure it is that joint where the grounds meet. Your last test would indicate you have ground through that though. It might be where you are touching the joint with the probes. If you are touching just the crimp it might have a solid ground so you should also try touching the wires. Personally I would have pulled that apart and twisted on a marrette and if that worked I would have soldered that joint.
Did you not already bench test the pump? If you got a solid 0 ohms on the wire side ground you should have then moved to the pump side and checked there. The problem could be the plug. That is part of the principle of testing you test both sides of every connection.
In simple terms using the test light you have the jumper in then touch the joint. No light then touch the wires that go in. Then keep moving closer to the pump until the light lights.
That said if it does not light at the joint it should not light near the pump. If I got those results I would suspect that the wire is near broken but rubbing on a ground in between those two places.
If it has been pinched off you might get enough ground to run the light but not enough to run the pump.
 
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