Air conditioning not working properly?

Thanks for the reply. The compressor does not engage in the dash only or floor only setting which it should not but does engage in the dash/floor combination setting, which should be fresh air only and compressor not engaged. It does engage in the two a/c settings: max a/c and a/c. It works correctly in all of the settings except dash/floor combination when it should not be engaged but is.

Thanks, Ken. The connections on the controller are 1 multi vacuum and 3 electrical all of which only fit one way. Kind of hard to do it wrong, but I understand you asking. I checked the ground under the left kick panel, it's good. I haven't managed to locate the dash panel right center support one yet. I'll try again to find it tomorrow. I'll let you know. Thanks for your help.
George.

Hi, Ken. Thanks. I checked the dash ground and it's good. Sorry to have bad news but I did what you suggested and double checked every vacuum line both under the dash and in the engine compartment, could not find anything wrong. I also pulled up a diagram of the fuses that told every system associated with each fuse and removed and tested everyone associated with the HVAC, waited 10 minutes and reinstalled them. No change. I know it's a frustrating problem and I really appreciate your time and effort with it. I see form the electrical diagrams that the PCM is tied into the system, could that be where the problem is coming from?
George