V1 Clutch relearn?

[Lndshrk Steve]

Taking a long shot to help me out. I'm checking what I can and I'm looking for the ground at the fuel pump relay. From what I see it is pin 85 on the relay, which grounds thru F2 @ X or C 3. But F2 (which I don't have a pin in) is for the LNF, for others it is B2 (Ground without LNF). I have no continuity between B2@ X3 and where pin 85 sits. I have no continuity in any of the 4 pins for the relay. Am I maybe missing something? Again, thanks for any and all help.

 

[Gtstorey]

You should have continuity from X3 B2 to pin 85 of the fuel pump relay. Could be a bad circuit in the fuse box. Are you checking from the pin on the fuse box for B2 or on the wire of the connector?
That X3 B2 ground is tied to a lot of the other relays.

 

[Lndshrk Steve]

I'm checking at the pin on the fuse box. I can't figure HOW the fuse box would mess up just this ground, or mess up anything. It worked before and everything I look at says B2 at X3 is the ground. I do have ground continuity for X3 at the B2 pin location. I'm stumped. Thanks for taking the time to look into it for me.

 

[Gtstorey]

Are you checking continuity on the B2 pin or the wire? If the wire then you may need to tighten the wire ind connector.

There have been issues with damaged boards from jumping the relay to manually force the pump to run.

 

[Lndshrk Steve]

Oh . . I did do that to drain the tank on the donor. But I'm checking at the B2 pin. I'll look for continuity from ANYWHERE to pin 85 of the fuel pump relay. Maybe I can find another path. Thanks.

 

[Gtstorey]

Check continuity between B2 and the other relays that it connects to and also check those other relays back to the fuel pump relay. If it a damaged board you might be able to repurpose on of those other relays to power the pump, depending on where the damage is.

 

[Lndshrk Steve]

I'll look into that, Thanks!

 

[Lndshrk Steve]

I checked and it seems I have NO grounds on my fuse box. So I pulled the bottom off and that looks good. If I remove all the fuses and relays, can I remove that top piece from the circuit board? I thought I'd ask before I pull everything off.

 

[Lndshrk Steve]

Ok. For those that want to know, once you move the tabs and pull the bottom off the fuse box, all you have to do is remove all relays and fuses . . . . and the circuit board falls out.

Unfortunately, my board looked fine. This doesn't seem to be my problem. I have no idea where my problem is, but it is not obvious here.

 

[Gtstorey]

By no ground in the fuse box are you talking about the ones I posted or you checked others? X1 B12 grounds the crank relay, X1 F9 grounds the air pump relay etc?

find pin X3 b2 on the bottom of the board and check continuity to the pins for the fuel pump relay on the top. One of those pins should be the ground. I think it will be the one labeled r12-86 but I’m playing with one out of the LNF.

 

[Gtstorey]

Post 30 edited since I had the wrong label for x3b2. My board doesn’t have that pin.
If you look close you can visually trace the circuit on the board. If you come to spots with holes in the board it transfers to the other side.

 

[Gtstorey]

You should also get continuity from the x3b2 pin and x2a6 and X1f3

 

[Gtstorey]

PM sent with phone number if you want to discuss.

 

[Gtstorey]

Is that a bad spot on the board circled in blue below, beside the J2-C3 label? I can't quite follow the traces in the picture but it looks like it might trace to R12-86 which should be the ground for the fuel pump relay.

 

[Desert Sasqwatch]

That is definitely a spot on the trace that got warm or worse. The only way to check is to measure resistance at the opposite ends that the trace connect to. You should be reading milliohms (less than 1 ohm) across this spot. Anything higher and it will need a jumper wire soldered point to point t to bypass the bad spot in the trace.

 

[Gtstorey]

Although it doesn't appear that the board labels are exactly the same it looks like it might be the same spot as burned out here;

Fuel Pump Not Priming

Definitely don't have a ground at pin 85, which I think should be the top left. Mine has 6v so that's an issue. From what I can tell there's some circuitry in the fuse box as that pin doesn't directly feed a wiring harness wire so I can't cheat the ground. Does anyone have a spare fuse box...

dfkitcar.com

 

[Lndshrk Steve]

Thank you guys for all the information and support! First thing tomorrow I'll pull the fuse box apart and put that spot under the digital microscope (just because I have one). Then we can get a good look and a picture of it. I'll keep you all informed.

 

[Lonny]

If you are going to add a jumper wire, don't try to jump from one side of the burned trace to the other side.

It is easier to find solder joints on each side of the burned trace and add a wire from solder joints to solder joint.

 

[Lndshrk Steve]

Here it is. Now I have to figure out where to fix it.

 

[Gtstorey]

I think I would go to the bottom of the board on the R12-86 terminal and solder a wire and and run it directly to ground or splice it to another of the existing ground wires. Another option would be to solder a jumper from R12-86 to (I think) R1-86.