Electrical woes....

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Kyle Childress

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There are several different layouts. The best way is to go to our front page, look up your vehicles electrical diagram and follow that.

I know that there are at least 2 feeds. 1 from the solenoid and 1 from the alternator.
Others have 1 for the headlights and 1 for the electric fan.

You've got it pretty tidy in there.
I'd also suggest you lose the yellow zip-ties and use velcro strips until you get everything fingered out.

The yellow zip ties were because I ran out of black...... so it was yellow or purple, I went with yellow, I felt it was the better choice. Behind all of that loom are magnets that have a place for zipties, they are amazing! Mr Gasket part number 3741G, I have those dudes everywhere.
 

Kyle Childress

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Here is how the H/L switch, T/L CTSY & HORN DM fuses are supplied with power. That circuit is protected only by the fusible link down at the solenoid - it does not pass through the FW junction block. If that link were burned it would explain the loss of H/L's and the other exterior lighting you mention (it would also knock out the horn and dome light). But it would not explain why you have no wipers. They are on a separate - ignition switched - feed:
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First check would be the fusible links - the ones that are connected to the starter solenoid. The wipers are probably an unrelated issue.

I think I see what I've done wrong, I don't believe I have the 2nd 12v hot wire running to the bus on the firewall, I believe I unhooked it when I was searching for my original issue. I have that exact wiring diagram printed off on 11x17s in the truck. It was a life saver, only thing are some color were different, I don't know if its because the colors have faded and changed over the years or if it was because my truck was originally a diesel.
 

Kyle Childress

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FOUND THE HEADLIGHT ISSUE! 12v for headlight had pulled out of the bulkhead. Now on to wipers.

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Kyle Childress

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You're next old buddy!

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Snoots

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As bad as that looks I'll bet that problem is in there too!
 

Kyle Childress

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Now have lights!, next issue....

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chengny

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I think I see what I've done wrong, I don't believe I have the 2nd 12v hot wire running to the bus on the firewall, I believe I unhooked it when I was searching for my original issue. I have that exact wiring diagram printed off on 11x17s in the truck. It was a life saver, only thing are some color were different, I don't know if its because the colors have faded and changed over the years or if it was because my truck was originally a diesel.

If you're interested, attached is pertinent section of the wiring diagram for the engine side of a 1979 with diesel. Note that the RED 2J circuit is run in the same manner as a gasoline engine (i.e. battery power at solenoid, through fusible link and then straight to the bulkhead connector block). Like a gas engine, it does not pass through the FW junction block or the JB fusible link.

On the cab side of the connector block, the 2J splits into two branch circuits. 2G (feeds fuses for T/L's, CTSY, HORN & DM) and 2F (feeds only H/L's):

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chengny

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I think I see what I've done wrong, I don't believe I have the 2nd 12v hot wire running to the bus on the firewall, I believe I unhooked it when I was searching for my original issue. I have that exact wiring diagram printed off on 11x17s in the truck. It was a life saver, only thing are some color were different, I don't know if its because the colors have faded and changed over the years or if it was because my truck was originally a diesel.

Ah, I get it. When you say "bus on the firewall", you mean the bulkhead connector block. I thought you were talking about the FW junction block.
 
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Kyle Childress

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Yeah I keep refering toit as a bus bar but i gues it really isnt, it's just a junction.
 

Kyle Childress

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Fix for headlights in place, got all the lights now. Next is windshield wipers thanks once again for the helpful advice.

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Snoots

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chengny to da rescue!

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Kyle Childress

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Figured out why my windshield wipers weren't working..... the brand new motor I bought was junk. Put one on it that was ancient from a old truck and boom. Working wipers now..... pretty irritated to say the least. Just wanted to thank you all again for the wiring knowledge and helping me figure it out.
 

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