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Old 09-18-2005, 06:15 PM   #1
Yukon Jack
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Electrical problem

Back before I had to take my heads of my engine all my electrical system worked. Now my dash lights don't work and I don't have parking lights or brake lights. I do have blinkers on the side markers and the back blinkers but not the ones on the grill. The headlights do work, but with them on the parking lights, brake lights, and dash lights still do not work.

The fuse block on the right upper hand side of the fuse block labeled something like Panel something does not have power. All the rest of the fuse locations have power.

Any thoughts on what I should be checking.
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Last edited by Yukon Jack; 09-18-2005 at 06:57 PM.
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Old 09-18-2005, 07:10 PM   #2
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Make sure the bulkhead connection is tightly screwed in.
The thing in the blue circle.
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Old 09-18-2005, 07:13 PM   #3
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Check the back of the fuse block where the wire comes in to the "panel" and see if it is in there tight. If not see if you can follow that wire and where it goes. That sounds like it is going to be your problem.
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Old 09-18-2005, 08:18 PM   #4
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I will hopefully get to look into the problem tonight. Thanks for pointing me in the right direction. Maybe it will be something simple.
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Old 09-18-2005, 11:37 PM   #5
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Got out tonight and I actually do have blinkers working on the grill. I had a bad bulb so that is fixed now.

Pulled the bulkhead apart and gave a good wiggle to all the wires without success.

The engine side of the wiring harness is new.

I pulled the wiring harness from the light switch to make sure it wasn't defective, and tried a different one. Still no brake lights or parking lights. Dash lights still don't work and notice the doom light is also not working. I can put the dash lights to a different post on the fuse box and they will work, but just don't dim.

It's very odd to me that the bulbs that double as blinkers and parking lights will only blink. That has to mean something.

I still can't get the fuse labled Panel something to have power. Could I run a hot wire to that location and see if that gets me going or would that possibly fry something?
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Old 09-19-2005, 12:26 AM   #6
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You are missing a ground. The dual filament bulbs that blink are the clue....they are grounding from one circuit, thru the other.
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Old 09-19-2005, 12:50 AM   #7
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Definitely a ground issue. Probally the ground that is found under the dash, coming off the harness that goes to the instrument cluster. I am not sure exactly where it is located on that era of truck, but on my 80, it is bolted to the parking brake bracket (doubt it is the same for your vintage, as I don't know if they have a pedal for an e-brake)
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Old 09-19-2005, 03:09 AM   #8
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Yukon. Did you maybe forget to reconnect your ground on your head or block when you reinstalled your heads? Just a thought, sounds like a ground problem. Doug
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Old 09-19-2005, 06:56 AM   #9
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Quote:
Originally Posted by Russell
Probally the ground that is found under the dash, coming off the harness that goes to the instrument cluster. I am not sure exactly where it is located on that era of truck
It's a 'clip on' end the generally can be found behind/near the gas guage.
Clips to the metal surround of the dash from behind.

Good luck YJ, simple is alwasy tough to find...
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Old 09-19-2005, 10:08 AM   #10
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Was a while back when I put the guages together, pretty positive I don't have a ground that is specific to just the gauge panel - to each guage, yes, but not to the panel itself.

Here is a pic of the back of the panel. The metal sourround is not in use anymore. It's odd that they worked a while back but not now.



I did remember to reattach the ground from the block to the frame. I don't think I removed a ground from the block to the cab, but I better check.

Hope I can get this figured out cause I'm headed to a show this weekend and there is a cruie in the evenings that is patroled heavily.
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Old 09-19-2005, 04:43 PM   #11
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Yukon Jack,
I have seen sparatic current issues when the dimmer and headlamp switch is bad.
all of those lighting issues you mentioned come through the headlamp switch. (I think you said you tried a different switch - I would try another yet) I would R&R the switch, check to see if both of the harness' are firmly plugged in (at the firewall) and that there are no bent forks inside the connections. Then I would by-pass the dimmer switch connecting the hot and the low-beam together. then you can start eleminating componets and wiring until you find the problem. I have to believe if you R&R the headlamp switch, this will solve your problem.
If you run a hot wire from the battery, then just temporarly supply the headlamp switch to see if you get lights everywhere. I am sure you have the schematic, if not let me know. you can find the line wire and make it hot and see what that gets you. If that works, then you have narrowed your search to the fuse panal.

Let me know what happens.
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Old 09-19-2005, 04:49 PM   #12
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I've got a manual with the schematic but sure have trouble figuring out what is what.

I know the headlamp switch I tried works so I'm pretty confident that is not the problem.

Does anyone know what the fuse labeled Panel that is circle here feeds? It is the one that is not getting power. I am pretty sure it feeds the dash lights but not sure if it also maybe gets power to the other things I am having problems with.
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Old 09-19-2005, 06:20 PM   #13
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These are the circuits you're having problems with:
Pnl = instrument panel
Tail Stop = Tail, stop and probably parking lamps & turn signals
Traffic = 4 way flashers

I'm trying to remember if you have a fusible link. Runs from the battery to the post on the fender beside the battery. Try jumping accross it to see if you burnt that with your short the other day. They can fry inside and still have the insulation on the outside. With the circuits involved, I am thinking either power feed or a major connector isn't working. I am also thinking the instrument panel is a different problem, from what we talked about Sunday.

Got my 52 back togther today. After I get some rest I'll see if I can figure out what might be wrong.
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Old 09-20-2005, 02:30 AM   #14
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Bump! Not sure what to tell you Mark, other than what has already been suggested. New paint might be the culprit in one of the connections mentioned above, not sure what all you had apart. Ain't restoration fun? LOL! Like Fred suggests, start with that first connection block close to the battery, it has been the culprit in my past!
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Old 09-22-2005, 12:12 AM   #15
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Just got my electrical problem figured out. It was all related to the switch that is activated by the brake pedal. It wasn't getting power. I hooked up a temporary bypass hot lead to it and everything works now. Took me about 3 to 4 hours in all to get it figured out.
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