Wife's '12 KK fan selector stuck on defrost

[RamV10]

We owned this KK for 10 years and it's never had any problems. All of the air from the fan comes out of the defroster and the outside dash vents. Is it a switch problem or the actuator or door not working?
Thanks for any suggestions,
Tony

 

[lfhoward]

Sorry to hear that. This happened to my 08 a few years ago and I needed to swap in a new air distribution box (basically a heater core dash-off repair). Details are here:

LOST JEEPS • View topic - HOW TO: Fix stuck HVAC mode door\actuator

Hopefully it is just a bad actuator and not a broken gear on the box.

 

[Krf]

It’s most likely the actuator or the mode door. OEM parts may not be available, but you can probably find aftermarket replacement parts. Will be a lot cheaper to replace either the door or actuator than the whole heater/evaporator box, but will probably be about the same work since a lot of the dash has to be taken apart to get to it.

Have you scanned the vehicle for trouble codes? The AC or body control modules usually throw a code when an actuator fails or a mode or blend door breaks.

 

[Tim 624]

We owned this KK for 10 years and it's never had any problems. All of the air from the fan comes out of the defroster and the outside dash vents. Is it a switch problem or the actuator or door not working?
Thanks for any suggestions,
Tony

I had the same problem check the vacuum line behind the coolant tank on the firewall my vacuum line deteriorated from the heat. I was able to fix it with some heat shrink tubing.

 

[lfhoward]

I had the same problem check the vacuum line behind the coolant tank on the firewall my vacuum line deteriorated from the heat. I was able to fix it with some heat shrink tubing.

Note: KJ’s have vacuum lines for the HVAC but KK’s have electric motors (actuators) to run the climate controls.

 

[ReniTheRenegade]

I would bet my left arm there is a broken tooth on the gear controlling the mode door. This happened with my 2011. Start with pulling the actuator off and confirm the gear on the actuator itself still turns when you move the directional knob. If no damage is present and it turns when you change fan direction, you can rule out the actuator. You do NOT have to completely dismantle the dash to pull the actuator and assembly out to inspect the teeth on the gears. But pay careful attention to how it is assembled so you can put it back together. There are a couple YT videos that provide a decent enough walk through on that.

With that said, if there's a broken tooth on gear that's on the distribution box, the whole box will have to be replaced and you can start tearing the dash out. Plenty of YT walk throughs on that.

 

[RamV10]

Among the many projects that I'm working on, I checked the actuators, both work. The gear for the mode door is broken, I've located the new distribution box and a Mopar seal kit. To be safe, I'm replacing the heater core too.
Thanks Guys,
Tony