I am having issues blending my heat in a 2013 jk. if its set to one set of vents it works fine like floor or dash or defrost, but if I set it to blend to dash and floor or floor and defrost it never does it. it sounds like the doors are getting closed and all the air gets stuck inside the dash until I change it to one location again. im thinking actuator but I don't know which one. I think there is 3 different ones. any help would be much appreciated

 

Here's a pretty good read https://azoffroading.com/blog/jeep-j...r-replacement/
I will be replacing my driver side blend door actuator this weekend, I got cold air only on driver side.

 

I wouldn't assume it's a blend door based upon cold air only on the driver side. All heater related problems have that same symptom. Inspecting the blend door to confirm it's working or not is a pretty simple test by doing the following.

1. The Easy/Not 100% certain inspection method: With the fan off, spin the temp dial quickly from hot to cold. While doing this, listen and you should be able to hear if the blend door is opening and closing since it makes a suction closing sound.
2. The 100% certain method: Use an inspection snake cam, and feed it in through the driver's side center vent and then downwards to the left/driver's side. That's the area the blend door is located and you should be able to see the blend door. Now use the temp dial and turn it from hot to cold and visually inspect if you can see the blend door fully open and close.

Here's some inspection cam pics I took of mine when inspecting, so you know what you're looking for.


The foam section is the actual blend door, and when you turn the temp dial quickly to the full hot position, you will hear when that door bumps up against that duct edge. Then also in the opposite direction as well.





Although the blend door is one of the common problems for poor heat performance in the JK, it is not an easy repair and usually takes small hands to replace it and you can't assume the blend door is the problem just by going by the symptom of cooler air coming out from the driver side vent. Now if you hear the clicking sound as shown in the video in that write-up, then that's a good indication the blend door is bad because what usually happens is that the plastic gear has stripped and that's what is making the clicking sound.

Even when the heat is working perfectly, the air coming from the driver's side vent is almost 20degF cooler from the driver side vent. Here is my theory of why that is the case, based upon how the JK's heater system works.


You can also put a thermometer in the passenger's side vent and confirm....although there is cooler air coming out from the driver side vent, your passenger side vent is likely only 20-30degF warner but not at 165-180deg like it should be.

When my heat was working perfectly, I measured 155degF from the driver's side vent, while the passenger's side vent was kicking out 175degF.

 

Thank you for the detail. I was going to remove the panel and duct (driver side) and expose the actuator so I can watch it and listen for it to operate.

 

Save yourself the trouble. I did that when I was originally trying to inspect mine. It's very difficult to actually see the actuator and the section you can see, you are unable to see the actuator move since the part that moves is on the opposite side.

 

I was going to take it down to this so I could see it. This is driver side.

 

Ahh the old days, makes one miss the days of stuff controlled by a cable. Just sayin.

 

The blend door is controlled electrically....no cable.

 

i get heat evenly through out but i cant blend the heat from say floor and vents or defrost and floor. it only works right if its set to one location like defrost or floor or vents

 

I know it's controlled electrically, in the days of cables all you had to do was keep them lubed.