15 lml 133k just recently noticed my tow haul is not working. When i press it the light DOES come on the dash but nothing changes driving wise. Couple weeks ago i had to replace my tcm due to it dieing while flashing a tune through ezlynk that had tcm tuning on it. I got a tcm with the factory calibration sent to me from a reputable vendor. (Im still waiting to here back from them.) I also went with new efilive tuning so i'm not sure if that has something to do with it (seems unlikely to me). My question is do you think the wire that is known to chafe on older trucks could be bad? I find it hard to believe seeing the truck shows the trailer dummy light on the dash when i turn tow haul on. I did some research but couldnt find anyone that had tow haul failure with the dummy light still working. Any insight is appreciated, i wanted to check here before i started pulling my steering column apart.