My Citadel (5.7 l 4WD) has just about every option on it, including the second row seat heat. I'm experiencing a very unusual malfunction with the seat, which my dealer 'can't duplicate' (favorite term) and I wondered if anyone here might have a suggestion.

The back left seat-heater will go on, and sometimes it stays on for a long time; at other times, it goes off after 7-9 minutes. Even after it's been off for a while and the seat has cooled off a bit, you can push the button, and it will stay on for only about 2 seconds before shutting off again (at either high or low setting). When it works, it kicks right up to temperature. But only stopping the vehicle, turning the engine off, and re-starting it at least once (and sometimes more than once) will get the heater to kick on and stay on again for any length of time.

The dealer says they got it to stay on just fine, and took temperature tests of the seats and found they matched each other very well. And it's only the left 2nd row seat. Any ideas? Thanks!