Easiest place to check for power in cab?

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Jrgunn5150

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I'm actually attempting to wire my truck correctly this year, and I've hit a bit of a snag.

Trying to start simple, because I'm simple lol. So power applied to the upper left wire in this pic, should result in 12v out on the missing wire in the pic correct? It's my understanding that the upper left is the 12v constant power feed to the cab, and the missing wire is switched out (to the coil stock). With 12v applied to the upper left, I'm not getting 12v on that pink wire so I need to know if I'm correct in my first assumption before I start my trouboeshooting.

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Frankenchevy

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With ignition switch on?

There’s no continuity from 12v constant(coming from firewall junction) to pink wire with ignition switch open. I had shifty continuity even closed until I replaced the switch.
 

Jrgunn5150

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With ignition switch on?

There’s no continuity from 12v constant(coming from firewall junction) to pink wire with ignition switch open. I had shifty continuity even closed until I replaced the switch.


With the switch on.

My intention, and understanding is, that I feed 12v into the cab via the upper left.

With the ignition switch forward I should get 12v back out from the missing pink wire. If I'm correct.

So if I'm correct, then I would suspect the ignition switch as well. To verify that, I'd like to check for 12v elsewhere in the fuse block.
 

Frankenchevy

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The blue arrow is on during run and crank, the green arrow only in run.
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Frankenchevy

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Your fuse block may look different. I don’t know anything about the earlier trucks.
 

Jrgunn5150

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So I have 12v, 12v at my headlight switch, but no 12v going to the ignition switch.
 

CSFJ

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Is the nuetral safety unplugged?
 

Jrgunn5150

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Is the nuetral safety unplugged?

It was converted from a 3 on the tree at some point.

I just ran a 10ga jumper from the bulkhead input part of the fuseblock to the ignition switch feed part of the fuseblock. It seems to function correctly now, although I'm not sure what I bypassed.

My harness is pretty butchered inside,I'll probably swap it out with a universal later in the summer.
 

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You might want to double check that however they modified it is still connected. I had a '79 once that the safety switch was jumpered. When the wire fell out, I was left with just lights and no ignition power similar to what you mentioned. I ran a jumper like you did so I could still drive it for a while, until I noticed the "U" shaped piece of wire on the floorboard. Plugged that back in, and had full power again.
 

Jrgunn5150

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You might want to double check that however they modified it is still connected. I had a '79 once that the safety switch was jumpered. When the wire fell out, I was left with just lights and no ignition power similar to what you mentioned. I ran a jumper like you did so I could still drive it for a while, until I noticed the "U" shaped piece of wire on the floorboard. Plugged that back in, and had full power again.

I'm pretty sure that's exactly what happened here as well.
 

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