Hey guys my name is Brian and I own The Seat Shop in Dallas TX, we work with tons of Chevy trucks and there are a few things that might be causing your heaters to not work. The way that GM designed the ON / OFF buttons on the door is really funky and causes a lot of confusion. On the drivers side door there are two buttons for the seat heaters, the button on the left will only turn on the seat back / top heater. When you push the left button 4 lights will turn on, there will be 1 light that is actually in the button that will light up and then 3 more lights to the right of the button will light up. The 3 additional lights that light up are next to the button on the right making it look like the bottom heaters are on as well but that is incorrect. The 3 lights are really the High, Medium, and Low setting for the seat top only. If you push the button on the left again the 3 lights will go down to 2 lights, push it again 1 light, push it again and all the lights will then turn off. If you push the button on the right it will turn on both the top and bottom heaters at the same time. The 3 lights will come on and they are now the High, Medium, Low settings for both the top and bottom heaters. The way that GM has the heaters wired you can turn on the seat top heater by itself but not the bottom. I talk with customers all the time that are simply hitting the wrong button on the door. GM's design for the indicator lights is very confusing making it really easy to think that the bottom heaters are not working. If a heating element is burnt out and you turn the heater on the lights will typically come on for a short amount of time (45sec to 3 min) and then will click off. If you are experiencing any other problems with the heaters not coming on or the heaters coming on and clicking off give me a call and I can walk you through all the steps to see what heaters might need to be replaced. Hope this helps. Thanks Brian for your expertise! Huge help! Apparently I've been using the controls backwards for the whole year I've had my denali! Seat heater works,just,fine. Wanted to ask your opinion. I love with a close family that I've known a lot of years. Between all,of us, there's 5 total GM full size suvs. A 2003, 2004, 2005, and my 2006,yukon xl,Denali. Plus a 2005 eksy esv. I know top,of the denalis are having seat heater issuesandnot because of the backwards co,trols. I went and played with the buttons to see what they were doing. In gonna try and get them fixed. Are there any signs as to differentiate between a heater element being bad or the module itself being bad?
