First time since I started a thread but if any of you guys follow me in IG, you saw my struggle to track down the cause of the CEL and VSC/TRAC lights coming on. Of course I started with the usual suspect of the gas cap and battery reset but the lights came back on after a short bit of driving.


Got the code read and it was P0705 for a malfunctioning Neutral Sensor Switch. One of the thing's I noticed that was odd was that the "R" on the PRNDL lights on the dash was illuminated brighter and whenever I pressed the brake or used my left/right signal or hazards, it would brighten even more.



After confirming from AutoZone that it wasn't a dying battery and it indeed was the P0705 code, I scoured the forums (both here and non-t4r) and came across a thread where they mentioned that a short in the trailer electrical connection can trip the CEL and letter illumination.

I know that on my first off-road trip, I broke that piece that holds the connector and the cover was long gone. Given the amount of muddy puddles I've gone through and the recent rain/snow, this had to be the cause of the issue.



Low and behold, there was a ton of mud and gunk in the connector, likely causing the short. I removed the connector and covered the left over plugs with a bag and a ton of zip ties. Hopped in the truck and no longer got the illuminated R light or any CEL's. Will confirm on my way to work tomorrow if it is a permanent fix.

Hopefully this is indeed the cause of the CEL and I don't have to dish out $150 to $200 for a new Neutral Sensor switch.

If anyone else runs into this issue, these are all the things I troubleshooted:
-Gas cap (most common cause of CEL/VSC/TRAC lights)
-Battery going bad
-Visually check connector to Neutral Sensor switch on transmission
-Check driver side floor area behind kick panel for water leaks
-Check grounds
-Check for any shorts in reverse/tail lights
-Recall any recent changes to reverse/tail lights or other electrical components
-Remove trailer hitch electrical connection

If this isn't the cause of the issue then I just wasted my time typing this up and will update it if that is the case haha!!


*UPDATE*
Drove about 30 miles commuting to work and back and no lights still so this seems to have been the cause of the issues!

Thank you so much for posting this. I got a Wilco Hitchgate and wired up the license plate light to the trailer wiring last weekend. Last night I drove with the lights on for the first time and got the CEL and the other lights.

I pulled the code, P0705, and did a Google search and this post came up. I went back and checked my wiring, and it turns out I'd connected the ground to the wrong socket in the hitch. Corrected the wiring and everything is happy now.

So thank you again!!