Finding the ground? Cooked all of my 12v receptacles.

[Searay45db]

on my 2005 gmc yukon XL i noticed my OBD II port was not working. There was no power to the port and I checked the Cig fuse as that is really where the problem is. Nope it was fine. The other night, I lost use of everyone of my 12v receptacles. When I pulled each on of them out, each one failed the ohm test. They were cooked. When I went to the dealer, I got the replacements. i checked the OBD II and the port now works. I only have one port getting 12 v's, the others only have about 4v's. Using a power probe, I am at a loss to figure out where I am shorting out.

Suggestions?

 

[Doubeleive]

wires may have melted together somewhere, you may need to start checking continuity from the adapter harness back to the fuse box

 

[Searay45db]

Trying to find the wiring harness diagram. Any idea? I have it ripped apart. One works.

 

[Doubeleive]

Trying to find the wiring harness diagram. Any idea? I have it ripped apart. One works.

I think the easiest way is to look up the gm up fitter diagram, you can find it online it shows a lot of the wiring and doesn't take a Einstein brain to figure out