Climate Control Issues

[shellback91 2,332]

Last year I noticed that when I started up the light on the vent control knob would occasionally blink for about 30-45 seconds before the climate control system would kick on. Other times it would just start working immediately. This behavior was sporadic which made it hard to decipher what caused it. I read that the Auto Temp Control Control was failing and needed to be replaced.  I finally had time to get it over to Joe and he replaced the part. Everything was fine for a week or so then it started acting up again.  Now it seems to happen more often that not.  I am having a hard time finding a possible cause other than the part that was just replaced. 

 

I read that there is a motherboard of sorts somewhere in the area but am unable to validate that or track the part down. Maybe my new part is a lemon? Is this normal?  If anyone has had this problem before I'd appreciate some thoughts on  it.  It is quite befuddling to say the least. 

 

-Marty

 

 

[Curly 1,329]

I don't have an answer, but found this description of why the light blinks.  The 14s in particular, but some others as well have had issues where the memory module is faulty and forgets where the blend doors are so it blinks while it runs it's relearn cycle.   

[jgaz 752]

This may have nothing at all to do with your problem but I’ll share it anyway.

My 2014 Dodge Caravan (not auto temp) had almost the exact symptoms as your JK.  
Once the control was done blinking the A/C worked fine.

When I finally had someone riding in the rear seat she told me there was a faint “clicking” noise coming from the rear A/C unit.   I could not hear it from the drivers seat at the time.  

I ended up replacing a rear blend door actuator motor.  
My thought is that when the motor was in the wrong position the A/C control was trying to reset it.

After the motor replacement the blinking control light did not reoccur. 

 

In my experience, if you need an actuator motor go with OEM.  The Dorman unit I tried in one other location was junk!   It failed TWICE!  
Yes it was warrantied but it was PITA to replace.

[theksmith 5,879]

if you want to troubleshoot yourself, i'd get a cheap OBD2 bluetooth adapter from Amazon and the OBD JScan app (iOS or Android). you can then pull trouble codes directly from the climate module to see what it's upset about.

 

it could be as simple as an actuator that needs replacing like @jgaz mentioned, or could be that you got a second faulty control unit. it could even be an intermittent wiring problem, particular with the can-bus lines.

 

without knowing what specific codes are being thrown, it's really a shot in the dark what to do next.

 

 

Edited June 12, 2025 by theksmith

[shellback91 2,332]

4 hours ago, jgaz said:

This may have nothing at all to do with your problem but I’ll share it anyway.

My 2014 Dodge Caravan (not auto temp) had almost the exact symptoms as your JK.  
Once the control was done blinking the A/C worked fine.

When I finally had someone riding in the rear seat she told me there was a faint “clicking” noise coming from the rear A/C unit.   I could not hear it from the drivers seat at the time.  

I ended up replacing a rear blend door actuator motor.  
My thought is that when the motor was in the wrong position the A/C control was trying to reset it.

After the motor replacement the blinking control light did not reoccur. 

 

In my experience, if you need an actuator motor go with OEM.  The Dorman unit I tried in one other location was junk!   It failed TWICE!  
Yes it was warrantied but it was PITA to replace.

 

3 hours ago, theksmith said:

if you want to troubleshoot yourself, i'd get a cheap OBD2 bluetooth adapter from Amazon and the OBD JScan app (iOS or Android). you can then pull trouble codes directly from the climate module to see what it's upset about.

 

it could be as simple as an actuator that needs replacing like @jgaz mentioned, or could be that you got a second faulty control unit. it could even be an intermittent wiring problem, particular with the can-bus lines.

 

without knowing what specific codes are being thrown, it's really a shot in the dark what to do next.

 

 

 

Thanks gents, I appreciate it. I have a plug in scanner that I forgot about, I'll give that a go before I buy a Bluetooth scanner.  Or I may just buy one just because. 

[SonoranWanderer 720]

On 6/12/2025 at 10:33 AM, shellback91 said:

 

 

Thanks gents, I appreciate it. I have a plug in scanner that I forgot about, I'll give that a go before I buy a Bluetooth scanner.  Or I may just buy one just because. 

 

Should definitely try what you have before buying, but stand alone scanners tend to be limited to which computers in the vehicle they can interact with. A proper bluetooth scanner with JScan can hit every single endpoint on the canbus for more indepth analysis. Whatever adapter you buy, make sure it's listed on JScan's site as "Highly Recommended", those are the ones that will read everything there is to read and can set/modify whatever JScan supports across the entire canbus.

I keep a (separate) OBDLink MX+ in each of my vehicles so it's always present the moment anything happens while on the road or trail. Usually so I can tell immediately which wheel speed sensor just broke (again).

[shellback91 2,332]

7 hours ago, SonoranWanderer said:

 

Should definitely try what you have before buying, but stand alone scanners tend to be limited to which computers in the vehicle they can interact with. A proper bluetooth scanner with JScan can hit every single endpoint on the canbus for more indepth analysis. Whatever adapter you buy, make sure it's listed on JScan's site as "Highly Recommended", those are the ones that will read everything there is to read and can set/modify whatever JScan supports across the entire canbus.

I keep a (separate) OBDLink MX+ in each of my vehicles so it's always present the moment anything happens while on the road or trail. Usually so I can tell immediately which wheel speed sensor just broke (again).

Thanks Woody. I have one of the old school cable ones and a funny thing happened.  I plugged it in, started up my Jeep and the A/C came right on. I am a trust but verify guy so I repeated the test. There was a short delay then A/C kicked right in, no codes.  I unplugged it and went on my way to whatever I was doing. The next time I started it(with the scanner unplugged of course) the blinking and delay thing happened. I am not seeing any codes when it does this so I may just get a Bluetooth one soon.

 

I went down a rabbit hole about this and a few folks say that this happens after the battery is swapped out for a "non traditional" battery or even after a regular battery swap. I am not sure I buy that ,however,  I think this started around the time I went from one of the traditional ones to an Optima.(My memory is crap these days) Coincidence, maybe, most likely actually.