Does anyone know if the A/C senses the outside temperature? I turned on the A/C when the temperature is cold (about 32F), but he compressor isn't turning on. Is it suppose to turn on or only when it'* warm outside?

even when you have the heat on the compressor will engage

I believe with the ECC the car knows what temp the air should blow at....so if its cold the car will not blow cold

When you have the heat on the compressor will engage ONLY IF IN AUTO. In economy it does not. And Pat, I don't think you're understanding the question here. He'* not trying to get it to blow cold air, he'* trying to get the compressor to engage in order to defog the windshield.

Crod, there is a minimum temp that the compressor won't engage at in order to kee the evap core from freezing. I don't recall what it is, but someone will chime in directly.

The compressor kicks off at about freezing temp to keep the evaporator core from becoming a solid block.

However other reading pointed to AC not coming on for regular cooling (not defog) below about 50 degrees exterior temperature.

Couple things to clarify...

The compressor will NEVER engage when the heat is turned on. It will only engage when the system is calling for A/C or defrost. That'* it.

And, it won't engage in the winter in a/c mode because the oil is so thick that will burn up the compressor. Nothing to do with the evaporator core.

This may differ on different years, but I have a custom feedback system on my 95SLE/sc that says otherwise.

If my ECC is in Auto, and it'* above the minimum temp, my compressor comes on regularly. Even in heat mode. This is normal. What dictates fan turnon is the AC compressor enable. I have an LED on my console that is illuminated if either the override is on or the compressor is enabled. It'* on any time I select Auto on the ECC (or defog front).

My car will not turn on the AC compressor even for defog if it is below 32° or somewhere in there. :? I was messing with that a couple weeks ago. Freezing cold weather - no A/C for defog.
But one day it was 45° and the compressor worked fine.

As long as the AC works for summer, and
As long as warm air hits the windshield for defog mode, I would not worry too much about it. When it is 100° outside and the AC compressor is not working, THEN you have a problem.

Keep in mind, other cars may work different, but our H'* seem pretty standard to what i just said, it is my experience. Apparently, many of our experience.

I think Bill and Vital both have reason.

The compressor doesn't engage if the temperature sensor is below 45 degrees or something like that. My 93 had the temperature sensor in the A pillar IIRC. If you have an automatic system it may use another sensor to get the protection minimum temperature reading. Also doesn't the freon lose vapor pressure as the temperature drops, so the system will sense a low freon pressure at the minimum pressure protection switch and won't engage either.

I can look up in manual for 93, 98, 03 if we really need to know the minimum operating temperature. And yes, my systems all would run in heat mode if the temperature is above that 45 degrees or 50. I usually operate in vent just to keep the compressor off and avoid the mileage drop.

anytime that i have the **** in a spot other that OFF on the CC the Compressor engages

Because you have the base CC panel. We don't. If we don't want the comp on, we can turn it off.