Ted D

Everything In Daniel Murphy's post looks exactly the same as the TrailBoss I have. The only thing that was slightly tricky was once you have all the screws out of the heater controls trim, pulled carefully on the right side of the heater control trim to release the clips securing it to the carrier/dash behind it. Still had resistance on left upper heater control trim. I had to carefully pull out very slightly on the information trim just enough to remove the heater control assembly, by sliding it downward from under the radio/upper dash trim. Then I was able to swap out the trailer brake control switch. Just an FYI I called by dealer parts dept with the part number from the switch I removed, and was told that that part was superseded/updated to the new part number. I have a hunch the old part number was pre-refresh stock/parts and the refresh software is not compatible.

I own my own repair shop. Purchased A 2022 Trail Boss in August. Alldata has the related PIT bulletin listed on 10-2022. I printed it out and took my truck in for the DRL recall, the trailer brake concern and the Wireless Phone charger update. They basically told me there was an information bulletin and GM was aware of the concern without a known fix, Something I already knew and they sent me on my way. Not satisfied, I called and opened a case with GM. Even more unsatisfied with the representatives answer, I ordered a 84488395 switch through my gm supplier and disassembled my dash. plugged the new switch in and no more message or returning code c159c. Looked at the part number of the removed switch, 87834257. Now if GM could get their crap together..Maybe I should apply 4 a job there.