2004 Yukon XL Heated Seats Help Needed

[bpopilek]

Hello, I am looking for some help concering the front heated seats in my truck.

About a month ago I was using my driver side seat heater when I noticed it wasn't warm anymore. I looked over and found the indicator light for the heater was off. Here is what happens:

When I push the buttons, I can hear a relay click under the dash, the indicator lights come on quickly, but then they go right back off. It does not matter if I choose upper or lower heaters, and it acts the same for both driver & passenger seats.

I connected up a Snap-On computer to it yesterday. We went under the driver door module and it shows the heated seats, but no error codes were present. It displayed the heated seat as inactive. When the button is pushed, it would show active for a split second, then go right back to inactive.

My mechanic friend thinks that it may be a shorted heater module. He isn't 100% sure on if that is the correct diagnosis, or where to locate the module. I believe it to be under the driver's seat, but I need to know what I am looking for. Also, would anything need to be reprogrammed in the vehicle's computer if that is the bad part and I swap it out with a new one? Or could it be a bad heater pad shorting it out? I did replace the bottom driver seat pad this past summer because the old one did not heat up any longer. With the cold weather here and cold leather seats, I am looking to get this fixed ASAP! Any help is greatly appreciated! Thanks for reading!

[kh090903]

You should check the resistance of the heater element, both bottom and back for both seats. I think you will find that the back element for your driver seat is open, whereas you should have some similar resistance from the other three elements. If the module doesn't sense the correct resistance, it shuts off the heater. That's why it won't work for back only, or for both the back and seat bottom. The connection for the element of both pads is under the seat.

[bpopilek]

I am not sure if you are correct on the bad heating element. The reason I say this is becuase the bottom driver side element was bad when I bought the truck. When I turned on the seats, the back but not the bottom would heat up. I bought a replacement element and installed it and everything was good again. That is why I am questioning it being a bad element because it didn't act this way when I knew that one of them was bad.

If you are pretty sure this is the case, I can check the element resistances. Do you know what the reading should normally be?

If it could be something else, where would I look? I can see the control module for both seats under the driver side seat, but not looking forward to ripping the whole seat apart to replace that if it is something different. Please let me know what you think and I will take a look at it this week again. Thanks!

[gmtech1]

The resistance value should be around 3 ohms.

[kh090903]

The resistance should be between 1.5 and 5.5 Ohms. When I tested mine, the back element was around 15 Ohms. When I got it apart, I had the burn marks on the element. If you test both the bottom and back elements and the Ohms are within spec, then you could have another issue. Use the link below to locate the electrical connection under the seat, so you will know which leads to test for both elements. I went ahead and tested the elements on the passenger seat too, and of all four elements, only the drivers back was out of spec. With the driver back element open, it will prevent you from using the the heat on the drivers side. In fact, something that really stumped me was my passenger seat worked just fine. If the passenger seat heat was on and I tried to turn on the drivers seat heat, it would automatically shut off the passenger seat heat.

Please post back after you test the resistance.

Link--> http://ww2.justanswer.com/uploads/Bl...s_diagnose.pdf

[bpopilek]

Ok, I know it's been a while, but I finally got a chance to check this out yesterday. The heat element that I replaced is actually defective. The resistance is out of limits and indicating a open circuit. So before I order another element for this, where is the best place to get one? If I just get one from the junk yard, what are some compatible vehicles that I could pull one from? Thanks!