It works fine on cool days and cool nights. It cuts off on hot days and will come on again only if I shut the engine off and back on again. The fact that it works fine when everything is cool leds me to the assumption that the ice out switch is not the problem. The fact that external heat is always a factor made me look for a faulty relay in the engine compartment and I couldn't find one Until SRI said to check behind the battery.
I haven't been able to check it out yet because we are having a cool spell and the AC is working. I've been having this problem since July of last year.