Tow/Haul button not working. (SOLVED) This is my first post here on GMT800 so "Hi everyone". My car is a Tahoe LT 2002 and my TOW/HAUL button have stopped working. There is no light up in dash and no difference on the gear up or down. I have a Haynes Repair Manual but I cannot find this button in any of the wiring diagram. Do anyone have any wiring diagram for this or some good advise how to troubleshoot this?