Yesterday I noticed that my ac compressor was cycling while the HVAC was on floor mode. I know it operates while in defrost, but it was for sure in floor.

Is that normal for these? I know it isn't for most vehicles, but everything has an acception.

Reason I ask is because I'm having heat issues. And everything plausible checks out ok. So right now nothing is making sense.

Also I have started my car and noticed a few times that my ac would be switched on. The light next to the snowflake was physically on. Also in floor mode.

 

Should not come on in floor mode unless the AC is physically turned on

 

Kind of thought so. Just making sure. Must have a switch issue.

 

Well now, I'm glad this is a current topic. My car is an 03 SS. I leave the zone selector to defrost and floor mix always in the winter. I also leave the A/C off (for obvious reasons in Illinois).
Last week, someone else had driven my car. The next day, I found my zone selector was set to floor and vent. Also, A/C was on. I set the climate control back exactly to the way I had it before, without thinking much of it.
Since then, the A/C has turned on at random. I'll start my car and it'll be on. I turn it off, then drive with it off for 2 miles without touching it and it will turn back on.

Now I can't say I've done enough research, but a friend with a 2007 Pontiac Grand Prix (with analog climate controls) said they experience the same thing. I'm not sure if theirs does it at random, or if they just don't know what they're doing.

 

This is exactly my issue...anyone find a fix?

 

To answer all your guys' questions. Without the A/C being selected, the compressor can still run on any mode between floor and full dash defrost, no matter the temp selected. All based on predetermined PCM programming. The light should never light up though unless you press the button.

 

exactly its turning itself on...what causes this?!

 

Most likely is the heater control head. Manual heater controls?

 

Does anyone think swapping this out would work? I hate having the compressor kick on when it doesn't need to - probably harder on gas mileage too.