03' Tahoe, No Power to diagnostic Port

First Time Poster

One of our friends has a 2003 Tahoe with the 5.3 liter, It recently threw a CEL. We went to plug in our code reader, and its getting no power from the connector. I was just wondering if anyone has ever dealt with a problem like this or has any ideas what we should check to fix it. Hope to hear back from some people.:thumbsup:

You need a "Hanes" manual or some other type of good scematic on the electrical system, a fluke meter or another good tester, and a beer. I have never had this problem on a car so someone else may know a better answer. But I chase electrical problems everyday, and it just takes time. First thing is to check the ground if it has one. But I'll bust out the Hanes manual tomarrow and take a look at the diagram if no one else has an answer first. JK can probly help a lot too.

First off, I think all the wires going to the plug are just a variable resistance for a ground. The wireing diagram is not something you can find in a Hanes manual. You will need the car on, or at least the ignition on to get the reading. Im sure you did, but just in case, now you know. But if you still have no power to get a reading, I would get the dealer to look at it. From what I see, troubleshooting this is not really something you want to do unless you have some experience with this type of problem. The problem seems like it would be between the computer and the plug... But I would have the GM tech look at it unless someone else has a better idea.....

The connector is fused via the cigarette lighter, if your cig lighter is out, you found your culprit, fuse is underhood I believe, replace it, back in business.

Aaron