So took the truck out the other night. Was driving fine for a bit. Shut down on the side of the road. Just cut out truck would fire right up and shut right down. You would think this would be the security system. Well what I noticed is my scanner wouldn't communicate with the engine management portion of the PCM unless the truck was running everything else it communicated with. I swapped the PCM out just to make sure and same thing happened. I feel that somewhere between these two transmission shops they damaged wiring somewhere or something just gave. Either way. There was an aftermarket security system with the remote start butchered into the truck that I had to cut the remote start wires because it was causing the truck to intimately shut off. So knowing all that what would cause the scanner to only communicate with one specific aspect of the PCM mainly the engine portion when running ? During all this i had a low voltage to the upstream O2 sensor that I had just replaced yet that code never repeated once the truck fire up an hour later and allowed me to drive home 🙄

 

Does the truck also have the factory security system?

 

No, they butchered in an aftermarket remote start system that I had to cut the wiring for the remote start feature because it was shutting the truck down it was a disaster. They just electrical taped. Everything together was horrible but it's such a proverbial cluster. F*** that I really don't even know where to begin. I didn't want to lose the keyless entry so I left it hooked up but it's bad I'll attach a picture for reference when I head out to the truck

 

If it wasn't a problem before the transmission work, it shouldn't be a problem now either...... Have you checked all the wiring harness that run near the trans to see if any of 'em got pinched during the removal/install?

 

Those **** bags @ the transmission shop didn't even secure the main trans wiring harness bracket to the stop of the bell housing and it's been in teens and low twenties so I've yet to climb under and remove at least the easier of the 2 bolts to get 1 into that metal bracket !

 

Well of course it has to be cold out when the truck gives you issues. That's an unwritten rule.