AC question

[tnchevy]

I have had my truck for a year now and there is one thing I still can't figure out and that is with the AC. I mostly manually control the temp but sometimes I will use the Auto function. I have noticed that if turn auto off it will still blow cold air until I turn it off Auto and Recirulate in the recirculate options. This cold air is AC air, not outside air. Am I missing something here or is it not working right. It has done this since I bought the truck and I have got used to it when I turn off Auto to go through and turn everything else off of Auto while I am at it. By the way the Cold air will still come out after I turn off the AC (light still stays on after I turn off Auto) while it is in recirculating mode.

[chuckl1218]

In my LTZ, I have the dual zone Auto AC. i believe this is normal as mine does the same thing. And I have come to understand that it works like you describe. And, don't forget that defrost will kick in AC in certain conditions. I just leave mine in Auto most of the time and not worry about it.

[tnchevy]

My LT also has the dual auto temp, glad to hear from someone else on this.

[TJay74]

I have had my truck for a year now and there is one thing I still can't figure out and that is with the AC. I mostly manually control the temp but sometimes I will use the Auto function. I have noticed that if turn auto off it will still blow cold air until I turn it off Auto and Recirulate in the recirculate options. This cold air is AC air, not outside air. Am I missing something here or is it not working right. It has done this since I bought the truck and I have got used to it when I turn off Auto to go through and turn everything else off of Auto while I am at it. By the way the Cold air will still come out after I turn off the AC (light still stays on after I turn off Auto) while it is in recirculating mode.

 

 

My truck did this exact thing, there is an update to the HVAC controller that will fix this. It will also make the HVAC work like the other GM cars while under remote start. Originally the HVAC would only operate from the state it was left in, after the update the HVAC will go until an auto mode based on inside and outside temps.

[tnchevy]

Thanks for sharing this, I assume it is something I will have to explain to the service guy the next time I bring it in. I still need to make an appointment to get my crappy FM radio reception looked at so hopefully they will fix this as well.

[chuckl1218]

My truck did this exact thing, there is an update to the HVAC controller that will fix this. It will also make the HVAC work like the other GM cars while under remote start. Originally the HVAC would only operate from the state it was left in, after the update the HVAC will go until an auto mode based on inside and outside temps.

I'll have to check this. I had the HVAC update done recently for remote start. ( FYI, it is PIT5240B, HVAC calibration update for remote start.) But I didn't check for this condition since the update. I'll check tomorrow. Thanks TJay!

[TJay74]

No problem, it was actually the main reason I had mine updated. That and I was having the same issue as the OP where I would turn off the AC and even though the light was off the compressor was still engaged and would stay that way until either key off or until I turned the HVAC off then back on.

[chuckl1218]

No problem, it was actually the main reason I had mine updated. That and I was having the same issue as the OP where I would turn off the AC and even though the light was off the compressor was still engaged and would stay that way until either key off or until I turned the HVAC off then back on.

Wow, I just checked...now if I hit the AC button when in Auto, it turns off like it's supposed to. Hit Auto and AC / fan run in Auto mode. I knew this fixed the remote start interaction with HVAC to work properly, but this is a nice surprise. It seems like it's always something, especially for early build units...