At a loss
Ok so backstory; I did the lifter release and vlom mod on my 2012 gmc Sierra 1500. I only disconnected the positive side of my battery and when moving my wiring harness back into place, the GROUND on the harness fell and touched the positive side of my battery. After getting everything back together and torqued to spec the truck starter doesnt always engage and when or if it finally does crank it runs for about 1-2 seconds and dies immediately after. I’ve pulled all fuses and replaced what was bad and all relays seem to be working as well. Starting to think that when the wiring harness ground touched the positive side of my battery that was still hooked up on the negative terminal I should add, I’m thinking maybe it messed up my ecm? On the dash it says reduced engine power and the stabilitrac and traction control crap is all there too. Service this service that. Anyone with outside knowledge or experience HELP PLEASE!!!
Depending on the size of the arc you seen if you seen one it's hard to say where to start. One thing for sure though is to target the p1682 code. For that code there is possibility of a fuse or relay issue. There's also the possibility that you melted something somewhere. There's a lot of talk about the fuse box wiring underneath the box on one of my sources of information. It was also mention for potential ECM failure. It could also be completely unrelated and be the ignition switch itself is failing. I definitely wouldn't rule that out since it tends to intermittently fire up.