I have a question I know that it is still cold outside here in Michigan my problem is when the ac pressure switch is plugged in the fans will turn on and the compressor starts working without me turning the ac on I can turn the temperature to cold it will get very cold like ac should even though it is 30 deg outside.the fans will turn and the compressor will just keep going until you disconnect the plug from the pressure switch.My car is a 2004 Chrysler Sebring Coupe 3.0

 

Do you have the controls set to "Defrost"? The A/C will come on when the defroster is turned on to dry the air as much as possible.

 

As above in post #2, or in defrost/floor position.
Also if your car is equipped with automatic temp control HVAC system, in its auto mode the a/c will be on also. You say you can turn down the temp and it gets colder, what about turning the temp UP for more heat? What happens then?

 

I had the heater on no defrost just regular vents, no automatic controls I can even turn the the settings to off and the radiator fans will keep turning and the compressor turning away,also when I turn the temperature from hot to cold it changes the air accordingly.

 

Have you tried checking (and removing) the A/C relay in the fuse panel? Could possibly be a bad relay there, stuck on.

 

It's unlikely to be a problem with the pressure switch itself. The function of the pressure switch is to shut down the compressor if the pressure gets too high or too low. If you disconnect the switch and the compressor shuts down, that's what it should do. Like Rebel says, you'll probably need to be looking elsewhere.

 

I will try the relay this weekend but remember this is a coupe 3.0 it has a compressor relay

 

You might want to scout out some Mitsubishi forums. The coupe was built by Mitsubishi. They may have some insight that could be lacking here.