We just bought a 2000 323i and it is our 1st BMW. Here's my issue: the a/c works and is cold when the compressor turns on. It will work sometimes and other times it will just blow hot air since the compressor is not turning on. The dash temp (which reads -40) displays & I thought this was the outside temp. Could this incorrect reading be causing my issue? We have switched it from manual to auto and get the same results. I read other threads and the the dial between the vents are set reflecting 3 blue dots, we know the a/c can get very cold, the compressor does turn on and off. Any help would be GREATLY appreciated.