Daddy-Butter

WOW - GMs standards for quality sure have sank over the years. Bad enough my 2021 Sierra X-31 has the upgraded BOSE system in it where the rear speakers barely produce sound even when faded to the rear, GM knows of this flaw and we just have to live with it, but I too have trailer light error messages coming across indicating my left lights are not working and/or the brakes lights on the trailer is not working. This only happens when it is raining out and it doesn't matter if it is with my small cargo/enclosed trailer or my open trailer I get.the same messages. Once there was a code so the dealership set an appointment and then when I brought it in, they said the code automatically clears out if the issue clears out. So it continues to happen and I took photos only to have them tell me unless they can duplicate, there is nothing to be done. This is a serious hazard that can result in an accident if not remedied and my truck is factory equipped with all the towing equipment including the brake controller. This same thing never occurred with my 2019 GMC Canyon that I traded in on this 2021 GMC Siera... All the common denominator is something is wrong with this trucks factory trailer light wiring... What to do???