Gauge cluster,tail lights and gas gauge problems

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Dman1049

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Didn't find any shorts. That orange wire goes to multiple fuses. Now all running lights come on when battery of truck is connected... Even without the headlight switch being plugged in
 

AuroraGirl

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Sure sounds like someone touched the wiring. A lot. Someone call CPS

Can you send a picture of your fusebox? Are all the glass fuses in the right spots and the right amperages? I have 78 owners manual i could show you the fuse box diagram and a 78 I can show what it generally looks like.

This is by no means a perfect example, but its what the under dash looks like of my 78. It probably was mostly OK, has some taps as you can see but that was for trailer wiring. Everything present and OK?
You must be registered for see images attach
 

Dman1049

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Found the front turn signal on passenger side full of water... Emptied and the problem was fixed with the tail lights. Found a grounded out spot in the pink fuel gauge wire. Gas gauge still doesn't work. Is there a way to test the gauge itself?
 

AuroraGirl

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Found the front turn signal on passenger side full of water... Emptied and the problem was fixed with the tail lights. Found a grounded out spot in the pink fuel gauge wire. Gas gauge still doesn't work. Is there a way to test the gauge itself?
does your gauge read full or empty? Mine reads past full but I have a switch and a power issue. Its grouned(the sender) fine. I believe an open circuit makes it read full. I could be wrong.

Do you have a dual gas tank setup or a single tank? If you have dual tanks, wiring to your switch should be accounted for. I have a switch that my wiring is broken to.
 

Grit dog

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Dman1049

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does your gauge read full or empty? Mine reads past full but I have a switch and a power issue. Its grouned(the sender) fine. I believe an open circuit makes it read full. I could be wrong.

Do you have a dual gas tank setup or a single tank? If you have dual tanks, wiring to your switch should be accounted for. I have a switch that my wiring is broken to.
Was dual now has a single Suburban tank in the rear. Took the gauge out of the cluster. No matter where the needle was the resistance didn't change. It's fun to chase multiple issues
 

AuroraGirl

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Was dual now has a single Suburban tank in the rear. Took the gauge out of the cluster. No matter where the needle was the resistance didn't change. It's fun to chase multiple issues
is your switch on the "right" tank. As in, i you used the wiring from the driver side tank did you have the switch point to driver side.
 

Dman1049

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Had wiring from both sides all joined so no matter where the switch is it will read a level. Have a new gauge on the way. Spendy
 

Dman1049

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So update... I pulled the fuse block and in cab harness completely out and dug through it. No shorts, gray dash feed wire was tied into all lights in the dash. Also all grounds were tied into one small 16 gauge wire. Made it where the dash feed wire only go to the gauges. Also made multiple grounds instead of just one.
 

Powerhouse Ranch

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So update... I pulled the fuse block and in cab harness completely out and dug through it. No shorts, gray dash feed wire was tied into all lights in the dash. Also all grounds were tied into one small 16 gauge wire. Made it where the dash feed wire only go to the gauges. Also made multiple grounds instead of just one.

and?
 

Dman1049

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Left it for the night. Didnt want to be disappointed. This was my last ditch effort. Already pricing out universal wiring harness because $600 to $700 is far too much. How many circuits does the truck really need is what im down to.
 

RecklessWOT

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Left it for the night. Didnt want to be disappointed. This was my last ditch effort. Already pricing out universal wiring harness because $600 to $700 is far too much. How many circuits does the truck really need is what im down to.
Instead of buying a whole new harness and going through the hassle of rewiring the entire truck you may actually want to consider bringing it to a shop. Gasp! I know I absolutely hate bringing vehicles to shops and generally refuse to (literally can count on one hand the times I've done over the years it after owning 30+ vehicles), but for something like wiring that I just absolutely cannot figure out I have actually brought two different trucks to two different shops over the years and both times it was less than $100. As much as a pain in the ass as wiring is for the average guy to deal with, for people who really know what they're doing it's no big deal.

Most likely just something stupid and they can usually find it pretty quick so it ends up being really cheap. Worst case scenario if something is completely ****** and would be complicated/expensive to fix, at least they can pinpoint it so you can go fix it yourself and you only owe a few bucks for diagnosis.
 

Powerhouse Ranch

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Instead of buying a whole new harness and going through the hassle of rewiring the entire truck you may actually want to consider bringing it to a shop. Gasp! I know I absolutely hate bringing vehicles to shops and generally refuse to (literally can count on one hand the times I've done over the years it after owning 30+ vehicles), but for something like wiring that I just absolutely cannot figure out I have actually brought two different trucks to two different shops over the years and both times it was less than $100. As much as a pain in the ass as wiring is for the average guy to deal with, for people who really know what they're doing it's no big deal.

Most likely just something stupid and they can usually find it pretty quick so it ends up being really cheap. Worst case scenario if something is completely ****** and would be complicated/expensive to fix, at least they can pinpoint it so you can go fix it yourself and you only owe a few bucks for diagnosis.

that's not a bad idea. just make sure you do your research and don't take it to just some half ass shop
 

AuroraGirl

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Ive always justfied my shop trips by considering how much money I have saved myself by NOT going to the shop, for example, the oil pan gasket on my old car. It would be 800+ for a shop just because of labor, but I did it for my swearing and getting covered in oil and a few hours and a 32 dollar gasket.

So, when my current car burst brake lines and it was an average of -20 out, I said Id eat 400 dollars for a shop to do all the brake lines because Ive earned that much.

The only other services Ive had done are tires(just a lot of work without a machine) and alignments.
I think you yourself can justify bringing it to a good shop, youve earned it.
 

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