Transfer case wiring

Tiny
WYSIWIGS
  • MEMBER
  • 1995 CHEVROLET TAHOE
  • 5.7L
  • 4WD
  • AUTOMATIC
  • 180,000 MILES
Hello,

4WD on my SUV listed above has stopped working. No light on floor unit and no engaging.

I have discovered the wire harness leading from the front axle/actuator back to the transfer case has been disconnected or broken. I have been told to connect the wire to the transfer case switch on top left of transfer case. It's a power lead to that switch, if that's correct. I'll be trying to locate and repair that over the weekend.

Here is my other problem with some broken wires that are toward the back top of transfer case, they appear to be "glued" to the back floor of the truck. There are two wires broken which might have to connect together? You can see in the picture which two wires and a white connector of some kind on the very bottom of the image. Is that a speed sensor, and should those two wires be connected together? If those aren't connected, what problems will I run into with 4wd operation?
The green/black wire might affect my fuel gauge system, that stopped working correctly years ago.

There is also a green/black wire leading off to the right that is frayed, but I haven't tracked down where that goes as yet. Any help there would be much appreciated.
In case anyone asks, I have already worked on the front wiring pigtails to the actuator etc. They were corroded and were replaced. Now I just need to connect that wire to transfer case and repair the others you see there.

Thank you!
Thursday, November 14th, 2019 AT 7:37 AM

8 Replies

Tiny
DANNY L
  • MECHANIC
  • 5,648 POSTS
Hello, I'm Danny.

Here is a tutorial showing how to test wiring:

https://www.2carpros.com/articles/how-to-check-wiring

I've attached below the transfer case wiring diagram you requested .I've cut the picture into 2 pieces to make larger.Hope this helps and thanks for using 2CarPros.
Was this
answer
helpful?
Yes
No
+1
Thursday, November 14th, 2019 AT 2:05 PM
Tiny
WYSIWIGS
  • MEMBER
  • 4 POSTS
Thank you, Danny. That diagram is going to help a lot! Question: Does the wire with the stripe at the bottom of the photo look gray and black to you? And the one to the right of it light blue? I haven't gotten under the vehicle yet today, it's bitter cold at the moment in the garage, so I haven't taken a closer look at those. I need to clean them up a bit to see the color a bit more clearly. Thanks again. :)
Was this
answer
helpful?
Yes
No
Friday, November 15th, 2019 AT 8:50 AM
Tiny
DANNY L
  • MECHANIC
  • 5,648 POSTS
Hello again,

Are you referring to the diagram I've provided or the picture you did? Let me know. Thanks again for using 2CarPros.
Danny-
Was this
answer
helpful?
Yes
No
Friday, November 15th, 2019 AT 4:39 PM
Tiny
WYSIWIGS
  • MEMBER
  • 4 POSTS
Sorry, was referring to my picture. On the diagram I can see a black/gray wire connected to the transfer case switch, and a light blue wire. In my photo I see what could be a black/gray wire and a blue wire coming out from the plastic connector(?) At the bottom right in the photo where the white arrows are.

This would indicate that IS my transfer switch, I hope. The broken wire above that with the wires sticking out of the end is a mystery to me as yet, (in the photo where the red arrow is)
Was this
answer
helpful?
Yes
No
Saturday, November 16th, 2019 AT 12:07 PM
Tiny
DANNY L
  • MECHANIC
  • 5,648 POSTS
Hello again,

As per the photo you provided that looks like a brown wire. If so, That would be the Brown wire the feeds to the transfer case switch on the second picture diagram I sent to you previously. See picture below circled in red. Hope this helps and thanks again for using 2CarPros.
Was this
answer
helpful?
Yes
No
Sunday, November 17th, 2019 AT 4:23 AM
Tiny
WYSIWIGS
  • MEMBER
  • 4 POSTS
I don't know what happened to my reply last night, but I don't see it here. So, if this is a repeat post, I apologize.
Danny, your diagrams and info were essential for this repair. Thank you so much.
I have repaired the wires and cleaned corrosion on the pigtail plugged into the transfer switch. I now have 4wd operating! I will need to replace the corroded plug, but it will have to wait for warmer weather.
Thank you again, this lady is a happy camper feeling safer on the winter roads here in Michigan.
Was this
answer
helpful?
Yes
No
Monday, November 18th, 2019 AT 10:04 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 42,861 POSTS
DANNY L is one of our best! Glad you could get it fixed, that kind of problem can be tough. Please use 2CarPros anytime we are here to help.
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 1:01 PM
Tiny
DANNY L
  • MECHANIC
  • 5,648 POSTS
You're welcome!
Glad to be of help. Hope you will use us again in the future. Thanks again for using 2CarPros.
Danny-
Was this
answer
helpful?
Yes
No
Thursday, November 21st, 2019 AT 1:45 PM

Please login or register to post a reply.

Sponsored links