Is there a way to override the "A/C unavailable below 40 degrees" ? I was driving in the fog and rain the other night and the outdoor temp was 37 degrees. My truck was fogged up like crazy. Without the A/C pump available to dry out the air it took forever to defog the glass. I would like to be able to push my A/C button and run the A/C compresser whenever I please. Is there a way to do this?


Thanks.





Gar

Your AC compressor should run whenever the defrost is selected. They have been that way for some years now to dehumidify the air as well as making sure the AC compressor gets exercised during the winter......http://www.dieselplace.com/forum/smileys/Cool.gif


Pop the hood and check it out, it won't run all the time, but should cycle on and off just like when the AC is turned on.

I always had trouble with my 01 and the climate control. When it would get a little warmer outside but still in need of some heat for defrost, it would only put out heat with the temp dial pegged.

GM does have some strange issues with the enviromental controls.

I always had trouble with my 01 and the climate control. When it would get a little warmer outside but still in need of some heat for defrost, it would only put out heat with the temp dial pegged.

GM does have some strange issues with the enviromental controls.


I thought it was just me and haven't figured it out yet....http://www.dieselplace.com/forum/smileys/Confused.gif


The climate control stuff certainly doesn't work as well nor is it as easy to operate as my Grand Cherokee.

Your AC compressor should run whenever the defrost is selected. They have been that way for some years now to dehumidify the air as well as making sure the AC compressor gets exercised during the winter......http://www.dieselplace.com/forum/smileys/Cool.gif


Pop the hood and check it out, it won't run all the time, but should cycle on and off just like when the AC is turned on.





Check the owners manual. For the LT with the dual climate control, the A/C compresser will not come on under any circumstances when the outside temp is below 40. It will blink 3 times and go off. Check the first paragraph on page 3-30 of the owners manual. I would like to be able to run the compresser, even on colder days, as it clears the fog much faster.





Gar

I haven't actually gone out and looked, and it's not cold enough here right now to verify that, but the AC indication on the dash doesn't come on with the defrost mode.


See Hoot's post above and try looking under the hood while the defrost is turned on. Maybe GM has changed something with the BCM that affects when the de-humidify function is supposed to work.


There have been some issues with the AC on these trucks which has been addressed in a few other threads. Whether or not that affects the defrost function or not I don't know. I do know that the Dmax takes so much longer to warm up, that unless you're driving it there's not much heat at all. I'm going to have to go out and see if the compressor comes on with the defrost now....http://www.dieselplace.com/forum/smileys/Confused.gif


edit info:


Okay I just went out and tried it. The AC compressor cycles when the defroster is turned on....http://www.dieselplace.com/forum/smileys/Approve.gif


Oh, one other thing, my GMC is the SLT which is setup with the same climate controls as your Chevy LT.Edited by: Zeeb

The compresser will come on if the temperature is above 40. My issue is that I wanna be able to dry out the air whenever the heck I feel like it. It was just a real bummer driving up Palomar Mountain the other night in the rain. As we got higher up, and the temperature dropped, I noticed the windows were all fogged up. I put it in defrost mode and it took forever to even marginally clear up the glass. The A/C compresser would not come on. The outside temperature I read on the mirror was 37. I first thought something was wrong, but now that I've read the owners manual, I found out it was just Big Brother GM looking out for my best interestshttp://www.dieselplace.com/forum/smileys/Ermm.gif Anyone out there know how to over ride this temperature dealio?





Gar

Your AC compressor should run whenever the defrost is selected. They have been that way for some years now to dehumidify the air as well as making sure the AC compressor gets exercised during the winter......http://www.dieselplace.com/forum/smileys/Cool.gif


Pop the hood and check it out, it won't run all the time, but should cycle on and off just like when the AC is turned on.





Check the owners manual. For the LT with the dual climate control, the A/C compresser will not come on under any circumstances when the outside temp is below 40. It will blink 3 times and go off. Check the first paragraph on page 3-30 of the owners manual. I would like to be able to run the compresser, even on colder days, as it clears the fog much faster.





Gar





When I took delivery of my '04 in December '03, I went through a check list for testing various accessories. On that day, the outside air temperature was around 35. My A/C would not come on because a temperature sensor was protecting the A/C components from damage due to colder ambient air temperatures. Ditto for the A/C activation by turning on the defrost.


IMO, the General is trying to avoid A/C warranty repair costs caused by A/C operation in freezing, or near freezing, weather. I think if you override the temperature sensor, you could damage your A/C system an void any warranty. http://www.dieselplace.com/forum/smileys/Ermm.gif

Does anyone know exactly where this temperature sensor is located?


I have run the A/C compresser in other vehicles when the temperature was below freezing on many occasions without any problems. It just clears the glass so much faster that I usually never turn the compresser off under any circumstances.





Gar

Gar -


I've had other GM and Chrysler/Daimler vehicles where the temp sensor was located just behind the grill or front bumper in front of the A/C condenser. I'm not the expert here, but if you disconnect it, you might see the BCM/ECM set a code. http://www.dieselplace.com/forum/smileys/Ermm.gif

I always had trouble with my 01 and the climate control. When it would get a little warmer outside but still in need of some heat for defrost, it would only put out heat with the temp dial pegged.

GM does have some strange issues with the enviromental controls.


I thought it was just me and haven't figured it out yet....http://www.dieselplace.com/forum/smileys/Confused.gif


The climate control stuff certainly doesn't work as well nor is it as easy to operate as my Grand Cherokee.

It seemed to work great in the winter. Set the temp and forget it. But as soon as outside temps got over 40 deg or so, no heat unless you set the temp on the red dot. Then you get too much.