Hi all,

Have recently had my 4.8 engine swapped in my 00' Silverado for a 5.3 from a 2 wheel drive Tahoe. Everything works great and runs fine apart from the 4 wheel drive.

I've found the problem, it's the wiring harness from the transfer case. I've traced the harness up into engine bay, and just underneath the fuse box on the drivers side it branches off to this plug, but nowhere to plug it. I believe it should go to the the fuse box, but there is nowhere to plug it. Maybe it needs an adapter? It's a three wire plug, any idea where it should go? And if it does go into the fuse box, could someone point me in the right direction to an adapter?

Many thanks

 

Anybody with a 99' - 02' 4x4 able to have a quick look to see what this plugs into?

 

I'll check my 2000 4.8 tomorrow. do you have a push button tcase or manual shift tcase?....they both have electronically controlled actuators in the front axle....is the plug on the axle for the actuator connected?

 

That would be great. That photo was taken standing at the drivers side fender, so it's at the rear of the under hood fuse box. I have the manual shift. I believe everything else is connected. I ran a live wire to this plug this evening, and the 4x4 engages just fine. I'm sure plugging it in will solve it, just finding where!

 

here are some pics

the connector is attached to the diff vent tube and I believe this loom runs down to the actuator on the front diff.

 

Thanks for taking the time to look at that. I have the plug you have, and that is plugged in at the right point. If you trace that loom back up a foot or so, it branches of in a Y shape, and that is the plug I need to find a home for. I've tried to get a picture of them both in shot. Vent tube plug connected at the bottom, other plug (purple) at the top.

 

I do not have that connector. the common connector that we do have goes up to another harness. this harness go into the underhood fuse box in one direction and down to the frame rail in the other.
I do have a std trans st truck so maybe my wiring harness is different.


what colours are the wires at the connector you are inquiring about. where does the other end of the harness go?


Something is strange about that connector; it's not wrapped in the factory type loom...or it that blue tape around a black loom?
Does your truck have a tow package or blunt cut wiring harness option?

 

It's an auto trans with manual 4x4 shift and tow package. It does have some loom casing missing, and it is just blue tape!



This photo of yours here, the loom I have looks to lie exactly the same way, that plug I have is on the end on the harness I have circled in your photo. Is this the one that plugs into another harness?

 

that harness you have circled goes into the cutout at the rear of the underhood fuse box....the other end of the harness goes down the frame rail


if you follow from my finger up the loom you can see it goes left to the frame rail and right, into the fuse box.
you may have to run some wires from that connector or take it back and ask what happened!
you need a wiring diagram to correct this.
the common connector that we share has 4 wires

black goes to grd
black/white goes to the pcm and ebcm
light blue goes to the transfer case
brown goes to the underhood fuse box

 

Everything you've stated I have too, and is wired correctly, except that part of the harness circled which, yours, runs up into the back of the fuse box, mine has that plug on the end. I've removed the fuse box, and there's no way that plug can plug into it. Guess I'll have to try and find a diagram somewhere and see what I can make work. Thanks for all your help.