Happens to mine too. HVAC module.
Ordered. Jk2014.

 

took an hour and all is good. part number 68197437ab

 

im curious to know , those that are replacing the HVAC control, if afterwords you start having the A/C compressor run after the wipers are on for a few minutes, even when you arent set in defrost or defrost / floor mix.. .

im a fan of using the A/C to defog the windows.. but I dont always want it to run when I dont need it too.. trying to figure out if what I have is normal behaviour or an errata condition.

-Christopher

 

I'm at the dealer for this right now. They're checking availability for the part #.

 

Mine has been perfect ever since the replacement..

and I am told by service its normal in the newer controllers for the A/C compressor to activate when the wipers are used to make sure the humidity level stays low in the cabin.. its also based on outside temperature, and if you have climate control inside temperature....

-Christopher

 

I'm having the same problem with my 13 JK.

Does anyone know what the replacement module costs installed?

Thanks

 

does anyone know the part number for Non-auto temp control? I need to order one.

 

I picked up a used 2013 from Carmax recently that had this issue. Took it back for warranty service and told them all the symptoms. I stopped short of telling them what part to replace. They came back saying this was "functioning as designed" and that the reason my defrost light is flashing is because it's looking for the hard top connection. I told them this JK never had a hard top, neither did my original JK (which was also a 2013) and it didn't exhibit this behavior. They stuck to their guns.

I bought the 3-knob control unit from the dealership and swapped it out myself today with a little help from a dash disassembly video on youtube. 20 minutes. It's fixed. No flashing defrost. No delayed HVAC response.

Tomorrow I'm going to talk to someone up the chain at Carmax and let them know that the 3 hours of diag their tech claimed is BS. With any luck, they'll reimburse me for the part, but I'm not holding my breath.

Thanks for this thread. Stuff like this drives me nuts and it was a really easy fix.

 

I have the same flashing Defrost light issue but I also had blend door actuators issues. I replaced the door but still have the flashing defrost light and delayed HVAC response. So did the swap of the three knob controller fix the problem? Is it still working great??

 

I have a 2014 Ram 3500 Limited and I had this happen at the same time my brothers '16 Charger had the same problem.



In my truck the mirror defrost button (i mistakenly thought this was my rear defrost button which my truck doesn't have) started blinking and didn't stop. While this was happening I couldn't change anything on my HVAC except fan speed. I couldn't even turn it off.



I took the truck to the dealership & the only remedy they could offer was flashing the ECM. I agreed & $115 dollars later it was still blinking. They then suggested that they could pull the whole dash & check the blend & recirc doors. I declined.



I pulled fuses, unhooked the battery - no fix. Same for my brother & his Challenger.



I finally changed the HVAC Control Module. OEM was $100 & the only tool required was a phillips screwdriver. The process took 10 minutes start to finish. I started the truck and the light started blinking but I held my breath. After the truck went through all its self checks, the light went off & all my controls worked. J did the same on his Challenger and his went back to normal as well. The light is the computer's way of telling you that self diagnosis has failed.



Apparently the module's memory can fill up and cause it to fail. Sometimes pulling the battery will cause the same thing.