I have just had my complete A/C system replaced. It has never blown real cold, blows for a very short time, then reads A/C Compressor off, low refrigerrant. The place where the dusplay & buttons

SOURCE: compressor working, cabin temp doesn't get to setting before system shuts off

sound like low side temperature sensor circuit open.check the compressor relay.

SOURCE: !987 Cadillac Allante A/C problem

i put a 1990 allante trans into my 1988 allante, the used trans was working fine before i put it into my '88 allante. now it shifts very rough and has trouble going into park and the linkeage is very stiff.....someone told me there is a transmission control module that could be the problem or some kind of vacuum control module????any ideas???..........thanks, rodney

SOURCE: the information center reads

You'll need to have the A/C system serviced. It is low on freon so the compressor isn't coming on, and you won't have any A/C. Usually you'll just need some freon.

SOURCE: My 96 Sedan DeVille Climate

This usually means the ac refridgerant is low. In Econ mode the ac compressor will not turn on, your car is staying in Econ to avoid damage to the compressor. If you are low on refrigerant it means you have a leak. Don't just buy a can and refil, have a professional shop check for leaks and fill the system with the proper oil and add refrigerant to the proper pressure.

SOURCE: my ac was blowing fine

If the car was retro fitted with R134a this was a common problem. There was a low side pressure sensor that needs to be changed. R134a runs different pressures than the r12.. When you go down the road the condenser cools off the system and the pressure drops below the minimum pressure. You need to make sure that the system is fully charged, not just cold to the feel. Both pipes coming out of the firewall need to be the same temp. this makes sure that the evaporator is flooded.
I hope this helped. Re-post if you need more info. Have a nice day and good luck.