2010 GMC Sierra Rear Park Assist Issue/Malfunciton

[Tyler Kneer]

Hey guys, I have a 2010 GMC Sierra SLE Crew Cab. I am having an odd issue with the rear parking assist throwing three different variations of codes on my dash. 

 

1. Service Park Assist (Most Common)

2. Park Assist Blocked (Never blocked, iced over, or trailer hitch installed)

3. Park Assis off 

 

My issues is that when I put it in reverse with the ebrake on I can go back and listen to the sensors and all of them work but one. Upon further inspection I swapped two sensors locations (i.e. removed two sensors and swapped sensor locations) the once seemed faulty sensor worked and the other working sensor stopped working.

 

This discover lead me to believe that I had a bad wiring harness. So I bought a new harness from Amazon and slapped it in and the same thing is happening. My next question is could it be the park assist module? I took the seat out and inspected the module connectors and wires and they look nearly brand new besides a thin layer of dust on the outside. 

 

I believe that all evidence points to the module, but I wanted to get some other opinions before I chucked any more money at it.

 

Appreciate any and all advice you have to offer.