need help

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rickbustedasstaho

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i have a 2004 chevy tahoe z71 to start this out my boss told me this has harness work work in my truck it was out of a 04 tahoe (base) so the ac plugs were didn’t was none digital and mine were digital, but I did not notice this until after the install … at the same time as I put an electric fans, a different computer for it that had non-four-wheel-drive and my gas gauge don’t work now my truck is stuck in four-wheel-drive. I think it’s just really hard into gear like it’s in four-wheel-drive, but it says it’s 2 Wheel Dr. but you can’t change it cause it doesn’t wanna change. It just says too high. i’ve been looking for a harness out of a Z 71 Tahoe. but my biggest question is, can you use a 2 Wheel Dr. computer for a four-wheel-drive truck? I hope this makes sense and please if you have something negative to say don’t say it at all. I don’t need that. I just some need help. Thank you.
 

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So are you saying that the engine compartment harness was changed? If so, how much of it?

Why was the harness changed?

Is this some kind of conversion from RWD to 4WD?
 
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rickbustedasstaho

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So are you saying that the engine compartment harness was changed? If so, how much of it?

Why was the harness changed?

Is this some kind of conversion from RWD to 4WD?

So are you saying that the engine compartment harness was changed? If so, how much of it?

Why was the harness changed?

Is this some kind of conversion from RWD to 4WD?
so no its always been 4 wd let me try to explain this not very good with explaining stuff so my harness was cut in all kinds of spots from a alarm systems and shit when I first bought the truck so I wanted to get this change the cause I was having issues and my boss gave me a harness out of a 2002 or it might be a 2003 base model Tahoe so it’s missing some things like the brake assist plug and there’s a couple other things I can think of but my gas gauge don’t work now my battery light staying on it’s stuck in four high and I don’t know if that’s caused from the computer. Why aren’t you or if I just **** some shit up? But the computer was changed out because I put electric fans in it and I just went to pick up Phone Chuck. I had electric fans in it so I took the computer and the fans and I tapped in my own wires, but it was only 2 Wheel Dr.. kind of jumped the gun on things so doing more research before I know all this I’m over my head….
 
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rickbustedasstaho

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i’m gonna put my old computer in right now. I just haven’t had the time to do it, but I will let you if shit changes
 
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rickbustedasstaho

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so I put my original computer back in it is fixed 90% of my problems. I just gotta figure out why it’s stuck and I believe for Will my front desk out right now because I broke it but it says it’s 2 Wheel Dr. but when I put it in gear, it’s jerks really hard like it’s in four wheel and doesn’t wanna go really
 

rockola1971

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You have to be very careful when swapping harnesses on a vehicle. Especially a truck chassis. The pinout at plugs, even at the PCM can be different on something as simple as a 2wd vs 4wd. Get it wrong and you have a vehicle fire. I recommend getting a known good harness for your application and installing it. car-part.com is the easiest way. Sometimes ebay can be a good source once you know the GM part# for your application. A 2wd PCM will not cut it in a 4wd application. The 2wd PCM wont even try to talk to a 4wd module. Then there is the case that the 4wd chassis has more options typically than the 2wd model so those options wont even be programmed in the 2wd PCM. Its like trying to shove Big Block Chevy into a Colorado while trying to use the original 6cyl Colorado PCM. It aint gonna work.
 
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rickbustedasstaho

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You have to be very careful when swapping harnesses on a vehicle. Especially a truck chassis. The pinout at plugs, even at the PCM can be different on something as simple as a 2wd vs 4wd. Get it wrong and you have a vehicle fire. I recommend getting a known good harness for your application and installing it. car-part.com is the easiest way. Sometimes ebay can be a good source once you know the GM part# for your application. A 2wd PCM will not cut it in a 4wd application. The 2wd PCM wont even try to talk to a 4wd module. Then there is the case that the 4wd chassis has more options typically than the 2wd model so those options wont even be programmed in the 2wd PCM. Its like trying to shove Big Block Chevy into a Colorado while trying to use the original 6cyl Colorado PCM. It aint gonna work.
yea indidnt changed the chassis harness. It was just a dashboard, but i it’s not 100% so i am going to just order the right one on that website u just gave me … i do appreciate the help … once i get a new harness for it i have to figure out turn on the fans .. my boss has the laptop but he don’t no how to just turn on the fans i guess.. he only has one program on there for the ls swaps we do in the old school we build …
 
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