02 Camaro Rear Defroster Won't Stay On

Thanks for reading. Here is the problem: When the rear defroster is turned on, it works fine for about 10 seconds, then turns off. If the button is pushed again, it just makes a mechanical clicking sound, and won’t turn back on. I am thinking it is the electrical switch. I replaced the little circuit board with one from a junkyard, but I am having the identical problem with this new part. When I took it to the dealership, they recommended that I get a new AC Control Unit (which is the part I just replaced from the junkyard, basically). If this is true, then I would have to assume that the part I just put in is defective as well.



What do you think I should do? A new AC Control unit runs around $240, whereas the junkyard part ran me $35. Problem is, I’m not even 100% sure that would fix my problem. It could be an entirely different cause?



Thanks in advance,

Steve

My guess would be a thermal protective device (fancy circuit breaker). They can wear out and do just that.

Thanks for the reply, Joseph.

Would this device be on the circuit board itself, or somewhere else in the car? The circuit board is only about 2"x2", and there is a small white box soldered on it. I’m willing to bet that this is the problem, but its just a hunch.

http://www.plccenter.com/buy/FUJI+ELECTRIC/56ND12W?source=AdWords_PN&gclid=CKrnt8Xox54CFU1M5QodYwz7sQ

This is a picture of the “white box” I mentioned. Apparently it is a relay. Could this cause the aforementioned problems?