do you happens to know which connector it is to the pcm? Have sprayed electric cleaner and greased them to protect them a while back when this first happened. But your right , maybe a wire pulled out or is cut somewhere. It would be nice if I could find i diagram that showed all of it. Also the connectors come apart right ? How do I do that ? Thanks again though I appreciate the help a lot.

 

Download the factory service manual for your truck from here. Wiring diagrams are in section 8W. You wanna look at transmission controls diagrams. That will tell you which connector, and which cavities on that connector.

 

I will do that! I have another harness with connectors it is burnt pretty good but computer connectors survived if I have to swap em. Thank you so much !! I will let you know if I fix it !!

 

welp , replaced the connector to the trans , re wired the pcm connector since there was a wire that seemed bad , still no fix. If I unplug the trans connector the code doesn’t come up. Plugged in a new harness and same code came back. Unplugged 02 sensors replaced upstream, still same code, if I unplug any speed sensor the truck seems to not care, which is odd. Also, the desired pressure for gps is no longer displayed on my scanner , and another thing is no longer displayed. It’s definitely a ground issue . The book shows all grounds and they are fine . Next step is I’m going to Hotwire the damn thing . If that doesn’t fix it , a match and gasoline will. Not like someone would give me what I want for it after dumping all this money into it anyways. Have even searched the harness for shorts with a short or open circuit finder

 

G100, witch is just in front of the battery, way the heck down there..... has about a dozen wires going to it... and while it may look good, on mine, most of the wires were corroded to the point that they "Tested" good, but, put a load on 'em, and they failed. Not to mention the ones that were just broken......

 

you mean where the harness goes into the fuse box ?? That’s all I got , abs module , fuse box , couple wires come off fuse box into battery temp and then headlights and grounds , cleaned all the grounds, not a lot of wires though. If not send a picture if you can please thank you

 

Nope. In FRONT of the battery, way down there below it, on the rail there. Its a common ground point... LOTS of wires go there.

 

I will check , appreciate it a lot thank you !!