Dual-Zone Automatic Temperature Control - blows cold air when colder than desired temp

S207307

Well-Known Member
Joined
Oct 6, 2017
Messages
114
Reaction score
48
Location
Kansas City
Vehicle(s)
2018 Jeep Wrangler (JL) Unlimited Sport S
I have a JLU Sport S with the "Dual-Zone Automatic Temperature Control". When I set the desired temperature to something that should require heat (say 71 when it is about 50/sunny outside, but definitely cooler than 71 in the interior cabin), it blows cool air quite often.
At first I thought the internal temperature thermometer/sensor might be in the direct sunlight and may be getting a wrong reading (it "reads" a higher temp than what I set in on the Uconnect display...and "thinks" it needs to cool to get down to the set temp).
It seems that when this occurs, I can jack the auto/desired temp way up (say, in the mid-80s) and it will begin blowing warm air again, so maybe there is something to the temperature sensor not getting an accurate internal/cab reading.
When I turn off "AUTO" it seems that I can properly control the blower -- no cool air when I don't want it.
I was wondering if anyone else noticed this problem and if they have suggestions.
I will mention it to the dealer when I take it in for an oil change in a month or so and see what they think as well.





Advertisement

 

$uicide$hift

Well-Known Member
First Name
Jeff
Joined
Feb 21, 2018
Messages
1,593
Reaction score
2,603
Location
Masshole
Vehicle(s)
2018 Jeep Wrangler Unlimited Sahara
Have you ever had an auto temp control option in a previous vehicle? I have and this is normal at least from my experience. The temperature inside your vehicle is much higher than the 50 degree outside temperature. To get to that 71 the system will not crank heat to get to 71 and then dial it back. 71 degree air will feel cool blowing directly on you where as you run at 98.6. Think of it being a warm summer day and jumping in a pool with a water temp of 71.

If the vents are directly aimed at you, aim them away from you. That air blowing directly on you will feel very cool.
 

PhoenixM3

Well-Known Member
Joined
Oct 28, 2017
Messages
137
Reaction score
132
Location
Colorado
Vehicle(s)
2013 GT500 and 2015 Fiesta ST
I have a JLU Sport S with the "Dual-Zone Automatic Temperature Control". When I set the desired temperature to something that should require heat (say 71 when it is about 50/sunny outside, but definitely cooler than 71 in the interior cabin), it blows cool air quite often.
At first I thought the internal temperature thermometer/sensor might be in the direct sunlight and may be getting a wrong reading (it "reads" a higher temp than what I set in on the Uconnect display...and "thinks" it needs to cool to get down to the set temp).
It seems that when this occurs, I can jack the auto/desired temp way up (say, in the mid-80s) and it will begin blowing warm air again, so maybe there is something to the temperature sensor not getting an accurate internal/cab reading.
When I turn off "AUTO" it seems that I can properly control the blower -- no cool air when I don't want it.
I was wondering if anyone else noticed this problem and if they have suggestions.
I will mention it to the dealer when I take it in for an oil change in a month or so and see what they think as well.
I’m going to guess that this may be a blend motor issue. May not be, but what you described is a symptom.
 
OP

S207307

Well-Known Member
Joined
Oct 6, 2017
Messages
114
Reaction score
48
Location
Kansas City
Vehicle(s)
2018 Jeep Wrangler (JL) Unlimited Sport S
  • Thread starter
  • Thread Starter
  • #4
I’m going to guess that this may be a blend motor issue. May not be, but what you described is a symptom.
Well maybe I can offer that as a talking point/suggestion when I visit the dealer.
You think it sounds like a blend door actuator or something else within that system?
 
OP

S207307

Well-Known Member
Joined
Oct 6, 2017
Messages
114
Reaction score
48
Location
Kansas City
Vehicle(s)
2018 Jeep Wrangler (JL) Unlimited Sport S
  • Thread starter
  • Thread Starter
  • #5
Have you ever had an auto temp control option in a previous vehicle? I have and this is normal at least from my experience. The temperature inside your vehicle is much higher than the 50 degree outside temperature. To get to that 71 the system will not crank heat to get to 71 and then dial it back. 71 degree air will feel cool blowing directly on you where as you run at 98.6. Think of it being a warm summer day and jumping in a pool with a water temp of 71.

If the vents are directly aimed at you, aim them away from you. That air blowing directly on you will feel very cool.
Yes, I have auto climate control in my two other vehicles.
I am used to cool air coming out at first -- it takes a little bit to warm the vehicle up so that it can produce warm air.
What I am experiencing is the Jeep blowing air somewhat normally, then after a bit (even though the cabin is still much cooler than the "desired" temperature) it begins to blow cool air -- as if it is trying to A/C the cab in order to cool it down (rather than warm it up -- as it still needs to be in order to get to the desired/set temperature range).
In other words, I would expect it to moderate the blowing and temp a bit IF the cab was warm or if it had been on a while and needed an adjustment...I just don't expect it to begin blowing a large amount of cold air after a bit of warming if I set my desired temp to be something like 70 and the cab is only up to about 50.
It is definitely abnormal as my wife even asked why I had the A/C on a few times (since cold air was blasting out of the vents) -- and this is something she hasn't ever had an issue with in our other vehicles (with automatic climate control).
 

cabnfvr

Well-Known Member
First Name
Tim
Joined
Apr 11, 2018
Messages
232
Reaction score
285
Location
Laurel Park NC
Vehicle(s)
2018 JLUL Sport
Occupation
Retired but working with benefits.
... What I am experiencing is the Jeep blowing air somewhat normally, then after a bit (even though the cabin is still much cooler than the "desired" temperature) it begins to blow cool air ....
Any update? our JL does the same thing. It's not a blend door issue (heat is correct, just that cool air flow). Turning off "Auto" solves the problem but that shouldn't be the solution.
 

alltimesaresoon

Well-Known Member
First Name
dave
Joined
Feb 21, 2018
Messages
632
Reaction score
1,329
Location
el paso
Vehicle(s)
fiat 124 spider abarth
i have the same problem. 39 outside, auto on, set to 72 degrees and blowing very cold and pretty high fan speed. no way out of it, even setting up to 80 and then to HI, except to take the auto off and go to manual, and turn off a/c and control the fan and temp on manual
 

cball508

Well-Known Member
First Name
Chris
Joined
Sep 15, 2018
Messages
79
Reaction score
56
Location
02777
Vehicle(s)
2018 JLU Rubicon
I had the same issue. Brought it to the dealer that did a re-calibration and I haven't had any issues since
 

ekohn00

Well-Known Member
Joined
Apr 2, 2019
Messages
179
Reaction score
95
Location
NoVA
Vehicle(s)
2019 Sahara Unlimited
Vehicle Showcase
1
I have this same problem. Has anyone else found a fix? Is the fix to bring it to the dealer for calibration?

Thanks
 

brewtus98

Well-Known Member
First Name
Bryan
Joined
Oct 5, 2018
Messages
223
Reaction score
307
Location
Toledo, Ohio
Vehicle(s)
2018 Sahara, 2003 TJ, 2004 TJ Rubicon
Vehicle Showcase
1
I had the same issue. I recently went in for my first service and they found a bulletin on the issue. I was told it was re-calibrated and I haven't had any issues since. Here's what was on my slip. Hope it helps

20181208_173111.jpg
I had the same issue. Brought it to the dealer that did a re-calibration and I haven't had any issues since
Ran across this in another thread. It appears this is what @cball508 had done. I have same condition and just switch to manual to stop the cooler air from blowing. Anyone have the text or a copy of the bulletin listed above?
 

brewtus98

Well-Known Member
First Name
Bryan
Joined
Oct 5, 2018
Messages
223
Reaction score
307
Location
Toledo, Ohio
Vehicle(s)
2018 Sahara, 2003 TJ, 2004 TJ Rubicon
Vehicle Showcase
1

smokymountain

Member
First Name
Andrew
Joined
Jan 31, 2019
Messages
6
Reaction score
2
Location
Maryville, TN
Vehicle(s)
2019 JLU Rubicon
I have had a similar problem with my heat / air. On vent and not on auto, the system puts out high heat until temp indicator hits around 68 degrees and then goes to what the temp is outside. I just want it to put out what the indicated temp is set. Also, the dual zone will randomly, unsync and the drivers side will be high heat and the passenger side will be cold. Temp control seems to work when on auto. Taking it in to the dealer Monday to have theme look at that issue and the loose steering. Mine's a 2019 JLUR w/ little over 3k miles.
 

brewtus98

Well-Known Member
First Name
Bryan
Joined
Oct 5, 2018
Messages
223
Reaction score
307
Location
Toledo, Ohio
Vehicle(s)
2018 Sahara, 2003 TJ, 2004 TJ Rubicon
Vehicle Showcase
1
It helped, but I think in the end, Jeep designed a sucky auto HVAC system.
Agreed. I didn't think the A/C even performed all that well in the hot/humid weather at end of last summer. Guess its not worth getting any updates to software controls done based on your experience.
 

Advertisement




Northridge4x4
 



Advertisement
Top