First, welcome to JCC and glad you are liking your KL!

Seeing your blower makes me want to pull mine and clean it....i thought you were going to say you found a piece of debris in there somewhere as that is what it sounds like to me. Have you been able to ascertain if it coming from any particular place? Possibly listen at each vent and see if it's louder or only there? Just have to wonder if something was in fact jostled loose as you drove and is now somewhere in a 'wind tunnel' making a racket, like when blowing on a blade of grass as a kid...

 

The noise is definitely loudest in the passenger footwell. It's hard to tell exactly where it's coming from but it seems like the blower motor area. I don't hear it coming from the vents or anywhere else.

I really thought there would be something in there as well. When I changed my cabin filter there were some long pine needles on it. Seems like the perfect thing to make a high pitched whistling noise... I looked around inside the HVAC tubing around the blower motor housing and it seemed free of debris aside from some dust. Could be that something is stuck somewhere else in the tubing.

If I’m feeling ambitious this weekend maybe I’ll pull it out again and try lubricating the motor. Although I’m not sure I can get to the bearing, I’ll have to check it out again. The service manual claims the motor and power module are non-serviceable and must be replaced together. Looks like it’s at least $100 for the power module.

 

Does the noise change when switching airflow or temp changes?

 

Not really, no. I’ve played around with it on max A/C, max heat and middle of the road temps the noise stays the same.

I’ve tried each airflow setting and they all sound basically the same. When I change the airflow configuration the noise will alter its character a bit. The pitch or frequency will change slightly. I think the variation is just from the different airflow in the vents.

 

Mine whistled when dealer didn't close the cabin filter cover properly. Have to make sure that cover is shut tight or it'll whistle.

Sent from my RS988 using Tapatalk

 

Is it possible to power up the blower motor when it's removed from its mounting to diagnose for certain whether noise is coming from motor or not?

 

It's possible. There are three connections from the wiring harness, I might be able to remove the motor and plug it back into the wiring harness to power it up. If I take it out again I may try that. Although the Jeep may be too smart to power it up when it's unmounted - considering how many sensors it has I wouldn't be surprised by this.

Mine whistled when dealer didn't close the cabin filter cover properly. Have to make sure that cover is shut tight or it'll whistle.

Sent from my RS988 using Tapatalk

That's a good thought. I push pretty firmly on the cover anytime I put it back and it does snap in on both ends. It's possible that it isn't forming a good seal. I'll look into that.

 

I think that one of the vent doors is slightly open when it should be closed. Going up the rocky road could have loosened something in one of the ducts, and now it is caught in the doorway. The slightly opened door could be creating a venturi: wind whistle through the narrow gap.

Also, cycle all the doors with the engine and blower off. If you hear a clicking sound, it might be one of the gears which control the doors. They are made of plastic, and if one of the gears is stripped, the corresponding door will not open or close properly: it could be that just one tooth is worn/broken!

 

Good idea. I gave this a shot earlier today when I was running errands. Unfortunately it doesn’t look like I can open and close the vent doors with the blower off. The vent position buttons don’t work on the Uconnect screen unless the HVAC system is on and the blower must be on. However, on the lowest blower setting I can hear the doors opening and closing clearly. They sound pretty normal, at least compared to what I’ve heard with other cars. I did notice that switching from top only vents to top and floor vents made a slightly different noise than the rest of the settings but no clicking and the vents blow air as they should in each mode. The whistling noise stays roughly the same in each mode.

Also, it’s hard to hear in the video I posted but the whistling has a characteristic spinning noise to it which is why I’m leaning toward it being the blower. I took another look at my service manual and I realized I can just bypass the power module and put 12VDC directly to the motor while it’s removed. Should work but I’m guessing it’ll run at full speed with 12V, I should probably secure it first haha. I wonder how cheap an adjustable DC power supply is, might be worth the investment.

 

You're not going crazy, I had the same issues and I think one of the vents on the passenger side was closed (but not completely closed and made the noise). Try opening all the vents and see if that works by chance.

 

I have the same problem and I went to the dealer and they told me that I must replace the blower but they don’t have it

 

Ever found a fix for this? having the same problems right now @benjmars

 

Mine is starting to squeak a little as well

 

Sounds like you need to replace the blower motor.

I just did this the other day on our Caravan actually, as it just started with a noise. Funny how much leaves/acorns/etc get in there, despite a cabin air filter.

Bought an aftermarket one off RockAuto and had it installed within 30 minutes of putting the van in my garage.

 

Hi Everyone! I've had my 2014 Cherokee Limited 4x4 for a little over a year now. It has about 33,000 miles. The warranty expired a little while ago. For the most part I love my Jeep! But the HVAC system has been very noisy with a high pitched whistle. I haven't been able to find any posts about the issue I'm having, hoping to find some ideas.

Link to video of the noise:

The noise started when I was driving up a short off road path to my cabin. Nothing serious just a 1/4 mile trail through the woods. It's mostly fixed rocks, I used to take my Acura RSX up the trail so it's nothing my Jeep can't handle. I'm not sure if the jostling of the trail had anything to do with the HVAC noise but it first happened as soon as I got up to the cabin so I figure it might be relevant.

It can be heard when the fan is on levels 1-4, loudest on 3. Beyond four the noise is still there but is drowned out by the blowing air. Turning the A/C or recirculate on/off doesn’t help either, as long as air is blowing the noise is there. The noise also seems to speed up and slow down with the fan so I first thought it was the blower motor. It can only be heard from inside the cabin. I don’t hear anything coming from the engine bay.

So far I have replaced the cabin air filter, which was filthy but that didn't help. Then today I removed the blower motor thinking that there might be some debris in there. There was nothing in there but the fins on the blower were really dusty. I cleaned them off pretty well with a pipe cleaner and put everything back together. No change in the noise. I attached a couple pictures of the motor and the dirty vs clean fins.

I’m not sure what to try next, maybe lubricate the bearing that the fins are on? Or maybe the noise is coming from somewhere else? Any ideas? I think the blower motor goes for about $50 on rock auto, I might be tempted to replace it just to see if that’s it.

I have a 2019 Cherokee. I also had a whistling sound start in the blower motor. I pulled off the kick panel cover on the passenger side and noticed the cabin filter was sticking out a little. I pushed the filter back in and turned on the blower motor and no more whistling.
Bottom line... with the filter slightly ajar the air was whistling around the the filter.
Thought I would share what I discovered with everyone.

 

I have a 2019 Cherokee. I also had a whistling sound start in the blower motor. I pulled off the kick panel cover on the passenger side and noticed the cabin filter was sticking out a little. I pushed the filter back in and turned on the blower motor and no more whistling.
Bottom line... with the filter slightly ajar the air was whistling around the the filter.
Thought I would share what I discovered with everyone.

This is dead on. I've experienced the exact same noise and root issue. In my case, I noticed that the small tabs the hold the cabin air filter end cap on were broken (likely when I changed it). There is still a good amount of friction so its possible for the cap to stay in place for a while before being forced ajar again. Easy fix once discovered.

 

Welcome from Utah!!! That's great information, thanks...😎

 

Took mine to the dealer for the same whistling problem - broken top latch on the cover. The service advisor pointed out two tabs on the cover that can be drilled out and the cover can then be attached with two screws (the housing has two pre-drilled tabs to receive the screws). Saved me the cost of a new cover..