Its really cold here, and i went to turn on my seat heater...And it doesnt work...turned the passanger on...it sure worked...The switch lights up...and after a bit of time...It switches from the three line light, to the single...Signifying the steady temp or whatever it means, How can this be fixed...and how much $$? Also, can I buy the heaters, and put them in the back seats? anyone done this?