Once in awhile I have noticed that the seat warmer will come on on its own. The issue would go away after a short period of time so I never really payed attention to it. However the other night it turned on again on HI and after 40 mins still hadn't turned off. I tried flipping the switch back and forth from LOW to off to HI and back but nothing. Finally I pulled off the frwy and pulled the fuse for the heated seats.
Has anyone else had this issue before? Or can point me in the right directions where to start looking. I'm thinking its either wires under the seat or the actual switch that's the cause. Any input is much appreciated.

 

Wish I could help, my mom's 2005 Suburban does this too.

 

I'm gonna say faulty switch. Easy DIY. Around $30 for the switch IIRC. Pretty sure there is a DIY for this in the Service Department. It may be under the lighting section...

 

I am having this problem also, I have an 05 TL, the weird part is, is that I pulled the fuse and the seat is still warm? mind boggling....?

 

Either a second fuse, or wrong fuse

 

Did you pull the correct fuse? Fuse 30 is a 7.5 amp fuse for the seat heater relay coil and fuse 15 is a 20 amp fuse for the actual heat element. If you pulled either of those, the seat heater cannot work, unless the relay is still pulled when you remove power from the coil by pulling fuse number 30. This would indicate a failed relay.

 

After studying the wiring diagram a bit, the only likely culprit here is the seat heat switch itself. I can't see another likely scenario which would do what you describe here.