1996 Cadillac sls--100.000 miles--just had the refrigerant checked and checked for leaks too. All was ok ! The air conditioner can be tripped on manually--but not using the controls on the dash. The people working on it say it never recognizes the command to " come on" using their scanner. They tell me it's either the heater/ac control panel or the ac programmer--any ideas which? And when I call around I'm always asked if it's digital--how do I tell? I'm told there is an electronic system and a non-electronic system? Again how does 1 discern which system it is? Thanks Mike S.