94 rcsb electrical issue

[Javlin42]

My 1994 rcsb has a new electric issue out of no where. Started with the tail/brake lights not working, but the 3rd brake light stayed on while the lights were in the on position.

I have a no crank no start. Super dim lights. When you press the brake pedal the dash and parking lights illuminate and the interior chime is audible. All interior fuses are good.

I'm about 99% sure it's a ground issue and have replaced the:
Bed to frame ground
Under heater core to engine ground
Under heater core to frame ground
Complete steering column that I had as a spare.
Battery

The battery is new and both cables look fairly new. But the one thing that throws me for a loop is I can put a jump box on the truck and get it to crank and occasionally start. I've downloaded the factory service manual however my phone isn't liking it very much.

On the interior, is the only grounds on the ds Under the dash? All the wiring I've replaced has been in good shape, nothing deteriorated or brittle. Have any of you all experienced anything like this?

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[clebouef98]

Im having a similar issue with mine, i actually just posted about it, what i have found so far is i have a short to ground on my park lamp circuit, only when the headlight switch is in the park lamp or on position, but the truck is acting almost identical to yours, mine fried the battery, i was able to remove the main power wire to the headlight circuit and was able to replace the battery and i am up and running and driving fine again, but have not found my issue yet, further diagnosis from that point is what lead me to finding the problem is only when headlight switch is on or on park lamps but i have not tried reconnecting that main circuit wire off of the junction box though, this may help or may be way different from yours but my truck was

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doing pretty much exactly what you described

 

[Javlin42]

I appreciate the input, I'm going to have another set of hands to help this weekend to work the key switch and going to start using my meter everywhere. And I got some replacement battery cables on the way too but I did remove the fuses 1 by 1 to try to isolate the issue but nothing changed, even with all fuses removed.

Seems like the issue is big enough to be right in my face. But I'll be more thorough this weekend and hopefully find the problem and post about it.

 

[clebouef98]

I appreciate the input, I'm going to have another set of hands to help this weekend to work the key switch and going to start using my meter everywhere. And I got some replacement battery cables on the way too but I did remove the fuses 1 by 1 to try to isolate the issue but nothing changed, even with all fuses removed.

Seems like the issue is big enough to be right in my face. But I'll be more thorough this weekend and hopefully find the problem and post about it.

If i find more on mine i will let you know, sounds like different issues but who knows

 

[Javlin42]

Figured I'd post an update to this. So I found that the starter solenoid wire was grounding to the tube that it runs through on the back of the block.

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Off the buss bar under the hood, the small glass fuse in this holder was full of corrosion as well as both contacts but cleaned up fine with a wire brush.

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Like stated previously I replaced the ground cable and trimmed the plastic off the back of the terminal protector and did the same for the positive side but I had some flickering still on the interior lights.

So on the buss bar there is a power feed to the interior fuse box, I had continuity from the buss bar to the other side of the link but when I switched it over to the meter I noticed noise on when moving the link around. I held the key switch to the start position and the link worked as it was designed to, popped and let the smoke out. And I came back into the harness and added a deutsch connector and some new 14g fuse link wire and everything is now working as it should.

 

[thinger2]

My 1994 rcsb has a new electric issue out of no where. Started with the tail/brake lights not working, but the 3rd brake light stayed on while the lights were in the on position.

I have a no crank no start. Super dim lights. When you press the brake pedal the dash and parking lights illuminate and the interior chime is audible. All interior fuses are good.

I'm about 99% sure it's a ground issue and have replaced the:
Bed to frame ground
Under heater core to engine ground
Under heater core to frame ground
Complete steering column that I had as a spare.
Battery

The battery is new and both cables look fairly new. But the one thing that throws me for a loop is I can put a jump box on the truck and get it to crank and occasionally start. I've downloaded the factory service manual however my phone isn't liking it very much.

On the interior, is the only grounds on the ds Under the dash? All the wiring I've replaced has been in good shape, nothing deteriorated or brittle. Have any of you all experienced anything like this?

You must be registered for see images attach

Probably the battery cables.
Factory GM side post cables rot internally.
The plastic end and the wire will look like brand new but if you cut them open they are rotted inside.
That is very common.
GM sidepost cables will look like brand new from the outside with a visual inspection and still be absolutly rotted green disintregated for a good 6 or 8 inches inside of the insulation.
If you buy a 30 year old ford with a top post connection and it looks like crap your first step would be to replace it before you tried to diagnose anything.
If you buy a 30 year old Chevy that connection is still garbage bad but you cant see it and it looks great.
The whole GM sidepost theory is just such horrible and dangerious engineering.
There is no advantage to be had in trying to maintain an old GM sidepost battery.
None.
You already need new battery cables so send those back and convert it to top post and go live your life.