HVAC is stuck on Defrost? What happened to my controls?

[richtj99]

Hi,

My wifes 2005 KJ Limited is having an issue with the blower controls. The controls for speed (1-4) work, the controls in the middle (pointing at head, or feet, or both, or recycle, etc) dont work, they are stuck on defroster (which I put it on yesterday) - Off works as well. The controls on the right (cold - hot) also are in working condition.

Any ideas on how to fix it?

Thanks,
Rich

 

[tjkj2002]

You have got a vacuum leak or the blend doors actuators went out.The defrost position is the default position.

 

[richtj99]

Is there a way for me to test which it is? i guess a leak is probably something I cant test, but the blend doors actuators, is that a replaceable part? If I pull the blower apart, is that something I can see?

Thanks for the fast response!

Rich

 

[jeepkj02]

Blend doors....I know they had a problem with that on the GC WJ's. Heard it was a huge pain to fix. Think you have to remove the dash.

 

[richtj99]

Is there a how to that explains removing the dash?

 

[JeepJeepster]

I would check into a vacuum leak before I assumed it was a blend door. Dont hear about the blend doors going bad on the kj.

 

[richtj99]

I hate to ask what might be an obvious question, but how do I check the vacuum to see about a leak? Can I do that myself?

 

[jnaut]

I hate to ask what might be an obvious question, but how do I check the vacuum to see about a leak? Can I do that myself?

I don't have it handy, but I believe that my Chilton's manual does a pretty good run-down on how to detect vacuum leaks in the HVAC system. I'd strongly recommend running by a good auto-parts store and picking up a manual if you're going to do this work yourself.