[littleDD]

Does anyone know the root cause of this loud clicking noise that happens on my 2015 451 just after turning the AC on? Here is some youtube video... https://youtu.be/beiSu263JXI . Eventually, I'll get it resolved via the warranty, but just wanted to post it on here.

 

[Smart Bob]

I would remove the blower motor & check inside the housing for a loose piece of paper or a business card. If someone put a card on your windshield, it can get pulled into the blower housing. This happened to one of our So Cal Smartie members.

 

[smark]

Take the car in for service. That noise should be covered under warranty.

 

[valvestem]

Loose squirrel cage on blower motor shaft or bad bearings?

 

[jimvw57]

I dropped my motor and broke the cage, it kind of worked after I glued it back together, until I replaced it.

 

[Niteshooter]

Does sounds like a card that has fallen into the blower assembly. Would have said leaf but that sounds a bit loud.

 

[littleDD]

It's difficult for me to get to and from the SMART dealer, especially when there is little motivation cuz the AC is still working. Also, my warranty is good until June 2019. I'll report back whenever I get it fixed. Thx.

 

[Smart Bob]

If there is a card or other item that has found it's way into your blower housing, warranty may not cover you.

 

[jetfuel]

..that's not a card...that's a hard metal to metal sound...
...it could just go away or just overheat the bearing...continue to bang away...spark and create a fire....
Jetfuel...get that thing looked at....just saying..

 

[littleDD]

Well, I discovered the clicking noise occurs not only after pressing the AC button... but also after pressing only the recirculate button (with the AC off) ... https://youtu.be/xPPPPOvxw60 . I really appreciate the advice...my plan now is to get it into service hopefully soon.

 

[jimvw57]

from the sound of it, I would take a look at the air blend doors and see if the gears are aligned or slipping. Get thee to a dealer!!

 

[Rustedwrench]

Air door actuator on the hvac case. Either the actuator's internal gears are stripped or something in the case is blocking the door and damaged the actuator.

 

[touchyu2]

On Electric Drive cars that would be the electric clutch engaging the separate electric motor that drives the AC compressor which is not driven from the main electric motor as would a gas car be driven. Your welcome!

 

[SkippyThorson]

I had to chime in because I know what this is. There's a small actuator that direct the air where to go, feet, face, windshield or any combination thereof with the control knob. Turn it elsewhere, and I'd bet it will behave itself in some places and others not.

As a Chevy guy, that sound haunts my dreams. The Impalas and Monte Carlos with dual climate control were riddled with 3 of those darn heat / AC blend door actuators. They're little motors that move a big plastic rotating housing which in turn rotates an opening where the air goes. They're comprised entirely of plastic gears, and one slip causes those gears to strip for life.

For GM cars, this little motor can be had for $40 at NAPA, and even less online from reputable places. There's only 2 bolts and one little wire clip, and this little encase motor can be swapped out. HOWEVER, that being said, I've never encountered this on the Smart, but I'd bet you that Impala there's some recirculation / air actuator motor that's the culprit. (Look up 2006-2012 Impala dash clicking videos and compare.)

 

[littleDD]

I got this fixed under warranty. The issue was... "Inspected door motors for A/C system and found the recirculation door motor case to have come apart due to internal binding, and, causing a clicking noise. Replaced recirculation door motor."

 

[jimvw57]

Good to know! thanks for the update!!