Well I recieved the dreaded phone call today from my wife, the A/C in her 1995 855T was blowing hot air. Thinking it was the dreaded evaporator problem I was just going to have the system recharged. I looked over the car today and I did not hear the distinctive sound of the A/C compressor cycling on and off. I checked the fuse ( #31, a 25A) thinking it may have blown but it is still good. Could we have a loose connection or is the compressor shot. If we have to replace the compressor what would the cost be ?? Any ideas ?

TIA

distinctive sound of the A/C compressor cycling on and off

Does any one know if the compressor also works when the heat is turned on?

If you have the A/C on, the A/C will work even if you have heat selected, It helps to remove the moisture from the air, a nice feature when it's raining and the inside of the car starts to fog up. The A/C is defalt on when you select the defrost position.

ONE THING YOU CAN CHECK IF YOU KNOW THE SYSTEM DOES NOT HAVE A LEAK IS THE LOW SIDE SWITCH MOUNTED BESIDE RIGHT SIDE COWL DRAIN TUBE. YOU CAN UNPLUG CONNECTOR AND JUMP THE TERMINALS TO START THE COMPRESSOR, DO N0T DO IT TO LONG THIS IS JUST TO SEE IF COMP IS OK. IF THE LIGHTS ON YOUR CC UNIT ARE FLASHING IN MEANS YOU HAVE DTC'S IN THE SYSTEM THA CAN BE READ USING A VST, BUT IF YOU HAVE A LEAK AND IT IS THE ORIGINAL EVAP IT IS A GOOD CHANCE IT IS THE EVAP. GET SOME TRACER DYE IN THE SYSTEM AND CHECK WITH A BLACK LIGHT.GOOD LUCK !

The a/c has a lot of sensors that check for pressure. I think it has 3 or 4.

When the freon pressure drops below certain point, the compressor won't start at all (to protect it). It happened to me last summer. In fact, I had to jump the cable to force it to start in order to draw in the freon. I probably have to do the same this summer.

Good luck.

Since you can not hear the AC compressor cycling, you may have a bad climate control system. If you have the electronic (Dual zone) AC system, you can pull the console out easily. Check the connections in the back. Also, the ECU records ECC errors. See if you can get any from the computer. I do not have the exact instructions, but I'm sure that the service manual can help. Also, are all of the other functions working with the AC? How about the LED for when you tunr the AC off? Do the lights on the AC and REC blink when you start the car? Also, did you check the fuse with an ohm meter? I have had a few that were not making good contact but tested fine. Anyhow, its a few places to look. Have fun.

Prospero