Given the voltage issues, it may be critical at this juncture for you to voltage test the fuel pump power pin grounded by the battery ground post. You may need to attach 5-10 feet of wire to the battery ground post to reach the black multimeter probe. The resulting voltage will serve as the approximate goal voltage to achieve using the fuel pump ground wire.

 

I still get the same 6-7V reading after doing this

 

I may be able to do that in a few hours when I have help available, but for now it's just me

 

Sorry, can you provide more details? You had re-spliced the ground wire to the connector pin. What form of the ground wire did you specifically test here.

 

I was thinking you were saying just to strip back a little bit of the X13795 wire without unsplicing what I had just done, and then connecting the black probe to that newly exposed X13975 wire, and the red probe to the power connector

 

Keep in mind that, at this point, you don't know whether there is a problem with the ground wire or the power wire with respect to the low voltage reading.

 

Should I start checking the power wire? If so, how would I go about that?

 

This^ works too. When you are able to run a wire from the battery ground post to the multimeter (keep wire as short as possible) where you are working, you'll be able to determine whether the low voltage is a power wire issue or a ground wire issue.

 

I figured out a way to do this by myself. When I use the battery as ground and measure the power pin, I still get around 7V

 

The downstream fuel pump circuit may have both voltage and ground issues.

How long is the ground wire from the battery and is its gauge size the same or larger than the two fuel pump wires?

What's the current voltage reading across the battery posts?

Are you still keeping the battery attached to the battery tender?

 

It's probably about 10 ft long. That wire is a 14ga where the fuel pump wires appear to be 16ga. So in short, it's larger than the fuel pump wires
Still holding at 12.6V
Yes

 

I'm sorry you're running into some problems. It must be frustrating. But I still think you are close to getting your fuel pump running. Hang in there.

 

Sounds good!

 

If I remember correctly, you jump terminal 30 to terminal 87 to send voltage to the fuel pump connector. Is this correct?

 

Yes, but it didn't do anything different when I tried it

 

Not sure what you mean here^, but you should start by measuring voltage individually at terminals 30 and 87 sockets to verify they have ~12.6V rather than 7V when the black meter probe is grounded by the wire attached to the battery post.

 

Installing the K96 relay rather than the jumper wire also should send voltage to the fuel pump. Is this worth a try now?

 

When doing that, I get a reading of 12.6V off of terminal 30, but only about 0.3V on terminal 87

 

That suggests poor contact of terminal 30 with the jumper wire or the jumper wire with terminal 87. Is it time re-install the relay?

 

I think I was misunderstanding what you were saying to do. I redid it and got 12.6V on both terminal 87 and terminal 30 this time. I'll go ahead and reinstall the K96 fuse. What's next?

 

Good.

I think you mean K96 relay. Have any of the tests done on the downstream fuel pump circuit been done with the K96 relay installed? Or has the jumper wire been used for all downstream tests?

 

All of the downstream tests have been done with the K96 relay, not with the jumper wire

Edit: To be thorough, I checked the voltage going to the fuel pump power connector grounded to the battery negative with the jumper wire still installed. I got the same 7V reading

 

Got it. I didn't know.

Two tests with relay installed:
Repeat voltage readings at fuel pump connector power pin comparing battery ground wire versus and the connector ground pin, which I'm unsure if it has been reinstalled into the fuel pump connector.

 

Looks like we sent our messages at the same time, but comparing the findings from my edit above and my findings from using the X13795 wire as ground (with the jumper still installed in place of K96), I got a little bit higher of a reading on the X13795 wire at 8V. So, in short, while still keeping the jumper wire in terminals 87 and 30, I got 7.5V using the battery as ground and 8V using the X13795 wire as ground.

I have reinstalled the ground pin into the connector already.

 

Sounds good. Can you do the same tests with relay installed just to be thorough?
But what your recent results suggest is that you only detect a problem on the power side of the downstream circuit rather than the ground side of the circuit. Do you agree?