I have this issue aswell and have kicked the dead horse over it again.
Below is a cut-n-paste from a reply, but to answer some questions;
In the shop for a couple of days with this "problem".
I was told the Limited and higher models have four sensors inside (dual zone ), laredo 1 or 2 (?) for a single zone
My sensors had a range of 70ish, 85ish, 105ish and 85ish. I don't know if that translates to degrees, but that would be too logical. They agreed that is was strange that cold air would come out with a 80 setting, but as the manual says that this "manual" mode is basically Automatic except the blower setting.
With that in mind, with a hot cabin this manual mode will try to reach that 80 by any means....even if you get cold air blowing out
I just want a real manual mode, up is hot, down is cold. I'm smart enough to regulate it myself.
In addition to that problem, I feel it changes temp output depending on if you're highway or city driving. High RPMS it gets hot...too many variations in temp
Dealer says its normal. I have now set it to 82 plus and/ or high and just regulate the window crack or vent blower speed.
p.s. here's my cut-n-paste from previous thread.
The HVAC system is a FAIL for me
. Sure it works somewhat... when the windows are up and you're cruising on the highway.
Today while driving with the sunroof open, 35 degrees outside with sun. Set at 80 on "manual" mode....oh sorry, pseudo manual. 10 minutes of hot, 10 minutes of fan, 10 minutes of cold air....and repeat. Reduce 10 minute interval to 5 minutes if you're changing the RPM's a bit.
Yes, I know I've written about this before and I hope I find that "ah-ha" moment soon on why the Jeep was designed that way.
Dealership says the Laredo Jeep functions as you would think....manual, But Limiteds and up ( maybe due to the 8.4a) function in this pseudo-manual.