Let’s slay this dragon…

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wildgoose

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Happy Thanksgiving yall… had a minute in between turkey and football to snap a few photos of my fuse box. This truck is an 84 diesel that has been swapped to a 454.

1. Anything y’all see obvious that needs to be addressed/corrected?

2. Any idea what the broken green wire with the black plastic fuse holder looking thing went to?

3. Dome light will not turn on… switches and bulb have been replaced. Still nothing.

4. I want to add a dedicated USB power panel in the cabin. Any recommendations on where to tap for power or go all the way to the battery?

5. What could be extra/not needed and likely can be removed?

Thanks yall

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wildgoose

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Snipped a zip tie and was able to make some progress in removing a few wires that weren’t terminated on either end so figured nothing can die that wasn’t already dead.

Also disconnected the horn as someone had removed it from the steering wheel and relocated it to a button under the dash… I can go without a horn for a while for the sake of clarity.

A bit easier to see what lives in here now…

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SquareRoot

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Looks like spaghetti has replaced the traditional turkey meal? You can get a wiring schematic from LMC for cheap. It's worth it.
 

Dmack

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Hate to state the obvious, but you will probably just have to start tracing wires to.see where they go. You will probably find one of the added wires will go to the HEI, since it wouldn't have that provision on a diesel.

My 83 also was a diesel to gas conversion. Mine was such a mess, I went to a junkyard and pulled a complete harness out of a gas square.
 

Ricko1966

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Okay for the guys doing gas swaps into diesels. Use the injection pump solenoid wire to control the ignition. Disregard/delete the glow plug wiring. All the other under hood wiring you need is all there and straight forward. Alternator,gauges,starter,air-conditioning.
 
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wildgoose

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Looks like spaghetti has replaced the traditional turkey meal? You can get a wiring schematic from LMC for cheap. It's worth it.
Is it just the same schematic in the wiring manual printed out?
 

wildgoose

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Hate to state the obvious, but you will probably just have to start tracing wires to.see where they go. You will probably find one of the added wires will go to the HEI, since it wouldn't have that provision on a diesel.

My 83 also was a diesel to gas conversion. Mine was such a mess, I went to a junkyard and pulled a complete harness out of a gas square.
I get it… there will always be a tracing job. No doubt I’ll have to track down where a lot of these go. But being new to these trucks, just hoping some of y’all might see something obvious and either point it out or make a recommendation.

Good idea… I need to find a junkyard around here that has a few trucks and see what I can find.
 

fast 99

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Any wire with a crimp on connector is not factory, such as the yellow wire near the flasher. Not saying that is all bad just trace it down. If not deleted make sure whatever it is powering doesn't overload that circuit.
 

SquareRoot

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Is it just the same schematic in the wiring manual printed out?
I'm not sure what the "wiring manual" looks like. It does show every circuit for all available options gas or diesel. I find it much easier to decipher on big 14 x 20 inch paper rather than on a screen.
 

wildgoose

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Any wire with a crimp on connector is not factory, such as the yellow wire near the flasher. Not saying that is all bad just trace it down. If not deleted make sure whatever it is powering doesn't overload that circuit.
Thanks!! Yeah that one is probably the first one I’m going to trace.

Also concerned about the fuses that a lower amp rating than what the fuse block is labeled.
 

Ricko1966

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Thanks!! Yeah that one is probably the first one I’m going to trace.

Also concerned about the fuses that a lower amp rating than what the fuse block is labeled.
I wouldn't worry about an amp rating too low,worst case it pops the fuse and you replace it with the correct fuse. Too high and you can fry wires or components.
 
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wildgoose

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Dome light has power standing one side of bulb, switches ground. Likely a broken wire under carpet drivers side.
Should both door switches have 2 wires connected to the switch? Driver side had 2 but passenger side only 1.
 

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