2005 Suburban LT, had for a number of years and just started having issues with the heated seats turning off. The problem is getting progressively worse. It affects both drivers and passenger side. Sometimes it works fine, other times as soon as you press the button it turns off over and over. Then other times it will turn on and stay on for a while, heat up fine then shut off.

I have just replaced the drivers side power window/mirror/lock control due to that going out. I was hoping that might be the issue but even the new power window module the heated seats still don't work.

Its obviously not a fuse. Does anyone know what all components there are to these systems? Since it affects both sides I'm thinking its not the door switch for the heated seats. Is there a module that controls both heated seats? If so could this be the cause and where is it located?

I've had several GMT800s but never had heated seat issues other than having to replace an element once.

 

Replace the relays. Modules control the power relays and relays do get weak or internally burn out over time.