Upfitter/pass thru wire screw up argh

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tahoeacr

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I guess at this point this is a rant. I think I know the issue. So, tonight I start to hook up my S8. I look in the manual of my 2019 and it says the upfitter wires are on the wire loom closest to the fender. These are the only ones I see. I unwrap them. Colors match what it describes in the manual. Since they're short as hell, I solder extensions on all the wires. Shrink wrap the solder joints and then shrink wrap the whole group. Crimp terminal connectors on the ends. Just before I put the wires in the 6 plug connector I decide to check voltage. Nothing. Check the fuses and they're good. Run out of patience so I go in and fix a margarita. Fire up FRF and do the search. I see that likely I hooked up to the pass thru wires which are commonly located in the wrong area on 18's.

so I guess my questions are,

1 Has anyone with a 19 ran into the wires in the wrong location?

2 Anyone who has used the pass thru wires are they different gauges? All six wires weren't the same gauge.

It just sucks to spend the time doing this knowing that I will never use the pass thru wires.
Thanks guys.
 

smurfslayer

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I sympathize. I have all but one up fitter spoken for on my 2017, and I’m assured by everyone here on FRF that Lucille --does-- have pass thru wires. I never found them.

Fortunately I had the powered wires found easily.

I read a bunch of folks found them fishing around the firewall, and I know you don’t wan to hear this but, you may need to take it to the stealership if you can’t get a handle on them in the engine bay.
 

rayofsi

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good luck in your search, in my 2018, my wires were bundled into the wiring bundle with the big connectors, i had to dig into them to fish them out.
my inside pass through wires were so far up. that getting them down with my fat arms, gave me a few cuts.
 

snt505

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Mine weren't too difficult to find. Just taped up under those two bundles on the passenger side. Sorry can't be more help. However, in regards to your second question, the pass through wires do have different gauges similar to the upfitter wires but colored differently.
 

V6Raptor

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On my ‘19, the “hot” wires were towards the drivers side. As for the gauges, I believe 1/2 are the same gauge, 3/4 the same, and 5/6. Can’t recall what gauges they were but I assume the pass thru wires gauges are the same as the “hot” wires.
 

onthebrake

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I have a '17 and I use the pass thru wires for my train horn switch and compressor and also with the upfitter switches for my cameras as well. Not sure what your issue is. All my wires are easy to find and to utilize. Passenger kick panel and under the hood at the firewall.
 

amREADY

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I have a 19 and trippple checked I was getting voltage to my upfitters and that they were the right ones for the right switch. I had read so many horror stories.

The upfitters were pretty easy to find and pass throughs were tougher, but findable in the engine bay. The max amperage is listed in the manual and 1/2 are higher than the others. So, that's right, they aren't all the same gauge.

The passthroughs in the passenger footwell were brutal to locate, cut free, fish down, etc.

Overall the upfitters, and passthroughs on each side of the firewall could have been a few inches longer and it would have made a huge difference.
 

Oldfart

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My pass throughs and my upfitter wires were both a royal pain in the ass to find. The upfitter wires had a large amount of tape over them wrapping them to anther wire run that made it VERY hard to tell what was what, until you started cutting open the tape. The upfitter wires were so high I had to use a real long pair of needle nose to start to pull them down, after jamming my head in that little hole for a while until I finally saw them. There was no way my arm could fit up as high as they were.

I also agree that if they were just a little longer it would have made it easier. Sure would be nice if the factory made it a little more straight forward.
 

pastorwug

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good luck in your search, in my 2018, my wires were bundled into the wiring bundle with the big connectors, i had to dig into them to fish them out.
my inside pass through wires were so far up. that getting them down with my fat arms, gave me a few cuts.
Same here! Bad design!
 
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tahoeacr

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Found the upfitter wires tonight. After unwrapping them, they would stretch to the battery. Stripped one and checked for voltage this time before I got carried away with things. My switches are hot with acces on engine off.
 
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