[SteveInfante]

So on my way to work in the 95+ degree heat my A/C wasn't blowing really well. The fan was set to 2, in Auto mode, non MAX. I upped the fan to see if that's what it was, didn't make any difference. I hit the MAX A/C button, didn't make a difference. Hit the defrost to see if it would cause the HVAC to shift the vent flap, didn't make a difference and wasn't blowing to the windshield either. It sounded as though all the air was blowing into my dash just behind the glove box. The fan sped up just fine, just no air was blowing out of my vents.

I had just had my car at the dealer for it's regular service. They didn't change the cabin filter, just oil and engine air filter. Now just for reference South Carolina doesn't have the best roads. I was still driving to work after calling the dealership to schedule an appt to have them look at it. I must have jarred something loose at some point. I had my sunroof open and the windows down when I felt cold air coming from the dash again (A/C was not activated, just the fan). I closed all the windows and hit the fan to speed it up and it was working as normal again. My best guess is that a flap that controls the air direction got stuck closed somehow and then freed itself.

Has anyone else had this happen to them. My car is a 2014 and has 33,750 ish miles on it. This is really the first mechanical issue I have had with my car. I've put just over 30K miles on it in 14 months of ownership. I cancelled the appt as I'm sure it would be wasted time due to them not being able to reproduce the event. If it happens again I guess I will drive straight there and just wait.

[moltenfire]

I have a Canadian 2015 M235i and something like what you experienced happened to me on a Michigan interstate last weekend. I was driving on the highway with the AC on and the cabin got gradually hotter and hotter. The weather outside was around 24-26C, so it's not that hot.

I noticed that there was a lot of fan sound coming from around the dash/windshield area, but not much air coming out of the vents. Setting it to manual and max AC didn't make any difference. After a while it seems like there was no AC at all.

I went to a parking lot and restarted the car, but it was not a cold reboot.

Got to my hotel and turned off the car. Opened up the hood and checked the front and rear fuse boxes, but no fuses blew.

Turned on the car again after about an hour, and everything's back to normal. I guess the car required a full cold reboot to get the AC working again. Super weird.

[Luminous]

Originally Posted by SteveInfante

So on my way to work in the 95+ degree heat my A/C wasn't blowing really well. The fan was set to 2, in Auto mode, non MAX. I upped the fan to see if that's what it was, didn't make any difference. I hit the MAX A/C button, didn't make a difference. Hit the defrost to see if it would cause the HVAC to shift the vent flap, didn't make a difference and wasn't blowing to the windshield either. It sounded as though all the air was blowing into my dash just behind the glove box. The fan sped up just fine, just no air was blowing out of my vents.

I had just had my car at the dealer for it's regular service. They didn't change the cabin filter, just oil and engine air filter. Now just for reference South Carolina doesn't have the best roads. I was still driving to work after calling the dealership to schedule an appt to have them look at it. I must have jarred something loose at some point. I had my sunroof open and the windows down when I felt cold air coming from the dash again (A/C was not activated, just the fan). I closed all the windows and hit the fan to speed it up and it was working as normal again. My best guess is that a flap that controls the air direction got stuck closed somehow and then freed itself.

Has anyone else had this happen to them. My car is a 2014 and has 33,750 ish miles on it. This is really the first mechanical issue I have had with my car. I've put just over 30K miles on it in 14 months of ownership. I cancelled the appt as I'm sure it would be wasted time due to them not being able to reproduce the event. If it happens again I guess I will drive straight there and just wait.

Wow, I'm so happy I found this thread. I had the exact same thing happen to me today. It was very hot out and extremely humid, noticed the exact same symptoms you mentioned with the air noise in the dash behind the glovebox. Drove home, restarted the car and it's been fine since. Just for reference I have a 2015 at 49.7k miles.

Coincidentally I was going to the dealer anyway to get a key read for an extended power train warranty I had just purchased (at only $100 over invoice, $650 below msrp and tax free!!) so I mentioned it to my SA who didn't seem concerned, said to "keep an eye on it"

[SteveInfante]

Originally Posted by Luminous

so I mentioned it to my SA who didn't seem concerned, said to "keep an eye on it"

Exactly! That's exactly why I decided to cancel the appointment. No use in me sitting there for an hour just to have them tell me to "Keep an eye on it". Stellar service. It's sad when you expect that kind of service.

[knotMoving]

This has happened to me twice in past 2 years and again right now!!! 84F outside baking sun and 80+% humidity.
3hrs driving to go until I park long enough for it to cool down completely

Damn frustrating

[Zoon]

This has happened to me twice on hot humid days on longer drives (hour+), once last year and once this year. It may be when you have the ac really cold but the fan on low the condenser will actually freeze up and blocks the output. I’ve been trying to keep my The fan higher on hot days now but haven’t tested it enough to confirm if that fixes the issue.

Also, I can’t remember where I heard this so I’m not sure how accurate it is.

[New_2_Guy]

This happened to me today. Two hours into a long drive with the AC on with fan set to about half speed. If I turned everything ( HVAC only I was still driving) off for about a half hour I could turn the ac back on and get lots of air blowing nice and cold but then the air would slowly decrease to no flow in about 5 minutes.

Does anyone have a fix for this?

[sethwas]

happened to me in a 428i while driving through death valley CA

solution was to turn it off then back on

Seth

[New_2_Guy]

https://static.nhtsa.gov/odi/tsbs/20...47927-9999.pdf

Found this. Looks like it is a known issue on the 3 series. Has anyone found a similar service bulletin for a 2 series?

[Kendapau]

Guys, new member of the forum here, long time car guy.

This issue may be due to the placement of the evaporator temperature sensor, which controls the computer system tied to the HVAC. Apparently the sensor is too close to the evaporator, and does not register correctly, and the system continues to cool until the evaporator eventually freezes over, blocking the air flow, resulting in the symptoms we experience. While possible, the issue is not necessarily related to low R134a.

The fix is described in BMW TSB SI B64 06 13

I have had my 2016 F23 228i Xdrive Convertible for a year now. This issue occurred in my car on a trip a few weeks ago. I took the car to a dealer in Maryland, on my way home from Delaware, and unfortunately they were not able to figure out the issue. They did a computer reflash but used the wrong TSB.

Monday I had the car at a larger dealer in MD. I had them check the R-134a level - it was fine. (Note that newer cars are switching to R-1234yf, a totally different topic). After getting the service manager involved, they updated the car with the correct TSB: BMW TSB SI B64 06 13

Link to TSB: https://www.tsbsearch.com/BMW/SI-B64-06-13

Cooling: Intermittent Reduction Of Air Flow This Service Information Bulletin (Revision 9) Supersedes Si B64 06 13 Dated June 2017. Customer May Complain Of Reduced Air Flow When The Air Conditioning System Is Operated For An Extended Time Usually Longer Than 30 Minutes. The Evaporator Starts To Freeze Up Due To The Position Of The Evaporator Temperature Sensor.

There are two "fixes" - for pre 9/30/2013, there is a spacer installation required using PN 64 11 9 950 495. For post 9/30/2013 cars the fix is to "perform a conversion in ISTA/P - Activate conversion to raise the minimum evaporator temperature".

I'm waiting for my next long trip to see if this update works. So far, so good.

Paul