2003 2500 with LQ4

[Gallant019]

I currently have a 2003 GMC 2500 with the 6.0 and 4L80E. I’ve been having issues with my neutral safety switch. I’ll put the truck in park, and the dash indicator it’s in 2nd gear, and will not start no matter where I move the column shifter. I’ve switched it out twice now in the since August.  I’ve also switched out the connectors.
 

I’ve bypassed the switch by using my starter relay and a jumper to the battery, and the truck starts that way. Once the trucks started, the dash indicator says that the vehicle is in park instead of 2nd gear. Once I turn the truck off, it’s back to 2nd gear. Disconnecting my battery terminal for 5 mins allows the dash indicator to read properly, but also only remedies this issue for a week or so. The only unfortunate thing about doing this method is the truck then throws a code for both my knock sensors after 2km of driving. I did replace both of them while I was doing my intake gasket back in July, but not the harness. 

While I was in the fuse box, there is junkyard markings on the panel, so I’m not sure if this could lead to issues if there is some wiring hacked up around there. The main harness looks good. 

 

I do have an HPTuner with available credits, but that would be last resort if there are other solutions.