I have a 2000 plymouth neon that the ac only works whne i apply the break. i have checked all fuses, relays, wiring and switches. I have swapped out parts and still have no resolution. For some reason everytim o hit the breaks the ac will work as designed. I can disconnect teh break switch and the ac works as designed, but i have no break lights then. Any one else ever have this issue? The dealership could not find any errors on the computer and had no error codes. I have swapped aout the break switches, air switches, fuses and relays and still no resolution. Any suggestions or advise will be greatly appreciated. You can replay directly to me at zachary@buchhorn.net or admin@buchhorn.net.

That is the strangest thing I have heard in a long time. It sounds like a short somewhere. Maybe a funky multi-function switch, but I don't know everything it handles. Good luck.

Well it obviously can't be the brake light switch if you disconnect it AND the a/c works fine, when at the same time the a/c works fine only when the brakes are applied??
The problem may very well be in the wire harness to the a/c compressor. I've seen wires break in the a/c clutch connector and in the harness side of the connector @8 inches from the connector itself. If you disconnect the a/c clutch connector and check the harness thoroughly you will likely find the problem. Then a little bit of soldering will have you on your way!