[ybkbmw]

Originally Posted by gIzzE

Once question you have not answered.

With the car set to AUTO, temp at 20ºc, blower how you like it speed wise, what is the issue?

No fresh air. I can see flap in recirculation mode. Button makes no difference.

[ybkbmw]

Originally Posted by gIzzE

OK, just went and tested it.

The button is not ignored,

On my car the button IS ignored when AC is on and over 20C outside, sometimes even when over 12C.

Originally Posted by gIzzE

my car does the same as yours, however, the noise you are hearing if the compressor kicking in, not the vents shutting.

From above fragment is not not clear to me which video matches your car behaviour https://vimeo.com/440448893 or https://vimeo.com/442124971 ? Please clarify.

[gIzzE]

First video is what my car does from standstill.
Drive for a bit, get heat in the coils and then the recirc flaps will open up and let fresh air in.

The second video you have forced recirc on while not in auto, while stood still it will remain on until you start driving, you have to turn off the climate to force the recirc off again if you're not driving.
Try that again with the system set to auto.
Try it again and drive off.

[gIzzE]

Originally Posted by ybkbmw

No fresh air. I can see flap in recirculation mode. Button makes no difference.

Sorry, what is the problem in the cabin?

Too hot? Too cold? Smells?

My guess is you have no problem other than you want to understand how the system works and it is annoying you.

If you stopped fucking around with it and let it do its job I bet it would do everything it is meant to do, which is keep the cabin at desired temperature and dehumidify it.

[HighlandPete]

Originally Posted by gIzzE

First video is what my car does from standstill.
Drive for a bit, get heat in the coils and then the recirc flaps will open up and let fresh air in.

The second video you have forced recirc on while not in auto, while stood still it will remain on until you start driving, you have to turn off the climate to force the recirc off again if you're not driving.
Try that again with the system set to auto.
Try it again and drive off.

Function when stationary, can be varied as you have clearly mentioned.

To the OP...

The other factor to note, when stationary the sniffer sensor can be picking up fumes and HVAC function is not a constant. What is controlling the cycle when you try a button pushing sequence? Humidity will change the parameters. As will ambient temperature inside/outside the cabin.

Hard to compare cars, or even the same car, in different settings and conditions. There is a lot going on, which means what happens one time you try a control sequence, is not the same the next time you try it.

How do I know... been there, trying to identify why my AUC (auto recirculation) function was not always acting fast enough and fumes were coming into the cabin. Don't expect an exact sequence when testing. I can get both your experiences, flicking through the buttons in my 5-series. It all depends... it's a complex system and is best left running fully Auto.

[ybkbmw]

Originally Posted by gIzzE

First video is what my car does from standstill.

Interesting, the first video is my car, in any mode auto or manual, A LED or no LED as soon as AC is on I see fresh air flap closes immediately if hot outside.

Originally Posted by gIzzE

Drive for a bit, get heat in the coils and then the recirc flaps will open up and let fresh air in.

Negative, even opposite. If I start from a cool garage system starts from fresh air. After getting on the street it soon switches fresh air off. I keep fresh air control in no LED lit position, AC itself is on auto. After that I don't get fresh air at all. BMW manual says: no LED = fresh air, no exceptions listed.

Originally Posted by gIzzE

The second video you have forced recirc on while not in auto, while stood still it will remain on until you start driving, you have to turn off the climate to force the recirc off again if you're not driving.
Try that again with the system set to auto.
Try it again and drive off.

Second video is a different BMW F30 where AC does not shut fresh air off. It may be unclear from the video but test scenario is absolutely identical to the first one. As I said above, even after 30 minutes of driving I don't get a breath of fresh air.

My questions still remain.
1. No observed behaviour matches BMW factory driver's manual. Yes, I heard that IHKA-High system firmware may be updated over time but I am referring to an online manual not the printed one.
2. Why AC immediately closes fresh air flap on one set of tested BMWs and does not touch fresh air flap on another set in absolutely identical weather conditions, baked under the bright summer sun next to each other on a parking lot.

[ybkbmw]

Originally Posted by HighlandPete

The other factor to note, when stationary the sniffer sensor can be picking up fumes

My tests don't involve AUC sensor functionality as I don't use A mode at all. I forgot where I read it, AUC sensor only active when LED A is lit. However here there is no mention of A mode:

Sensor for automatic air recirculation mode

The AUC sensor is a metal oxide sensor. This sensor is highly sensitive to various smells and pollutants that are typical of traffic.

The AUC sensor evaluates the concentration of carbon monoxide and nitrogen oxides in the intake fresh air. The AUC sensor converts the detected air quality (also referred as air grade) into an electrical signal. To simplify processing of the information, the air quality in divided into 10 grades:

• Grade 0 to 10 (clean to severely contaminated)

The AUC sensor transmits the corresponding grade as a digital signal via the LIN bus to the junction box electronics (JBE). The junction box electronics transmit the digital signal via the CAN bus to the IHKA control unit. If the automatic air recirculation control sensor measures an emission value that is too high, an automatic changeover recirculated air operation takes place via the IHKA control unit.

Question: is there a chance that AUC sensor sends false signal and overrides no LED fresh air mode?...

[HighlandPete]

Originally Posted by ybkbmw

My tests don't involve AUC sensor functionality as I don't use A mode at all. I forgot where I read it, AUC sensor only active when LED A is lit. However here there is no mention of A mode:


Question: is there a chance that AUC sensor sends false signal and overrides no LED fresh air mode?...

AUC function could help you see if there is a direct problem with air flow function.

Recirculated air should not be a constant function in AUC position. The following (not specific for the F30) illustrates the typical strategy.

Automatic Air-recirculation Control

If the AUC II sensor detects an increased level of pollutants in the environment from spark-ignition and diesel engines, the IHKA control unit will automatically switch to air recirculation mode.

To make sure there is still an adequate supply of fresh air, air recirculation is only available for a limited time:

• At ambient temperatures less than 0°C: 2 minute re-circulated air mode -> 20 seconds fresh air mode -> 2 minute re-circulated air mode -> etc.
• At ambient temperatures from 0°C to 6°C: 3 minute re-circulated air mode -> 20 seconds fresh air mode -> 3 minute recirculated air mode -> etc.
• Operation without a/c function at ambient temperatures greater than 6°C: 4 minute re-circulated air mode -> 20 seconds fresh air mode -> 4 minute re-circulated air mode -> etc.
• Operation with a/c function at ambient temperatures greater than 6°C: 12 minute re-circulated air mode -> 20 seconds fresh air mode -> 12 minute re-circulated air mode -> etc.

When the engine is started and the AUC function activated, fresh air mode is always selected for about. 40 seconds due to the warming phase of the AUC sensor.

As to the AUC sensor being faulty, I don't know if the sensor can have that mode of failure. If it can fail that way, the above explanation for introduction of fresh air pulses, indicates the system should still override a 100% 'positive' signal from the sensor. AUC sensor can lose sensitivity over time, I'd suggest that mode of failure would leave the system open to 'outside air' more often.

It does appear you have some kind of fault, if you don't get any fresh air with AC running. Comparison to other cars, particularly when stationary, could be a red herring, due to lots of variables which may mask the real issue. Best course is live data while driving. If BMW take it seriously, there is the chance they will put a data logger in the car and interrogate after test runs, or you using the car for a few days.

I've personally had a data logger in an E91, to see why my HVAC system did strange things while driving. (Long story short, there was a humidity issue). Also my dealer has run a laptop in my current F11, to identify if the AUC sensor was functioning correctly. Was the simplest way to prove its function.

[ybkbmw]

Originally Posted by HighlandPete

my dealer has run a laptop in my current F11, to identify if the AUC sensor was functioning correctly. Was the simplest way to prove its function.

Running a data logger is the most obvious first step but mine says they don't have it.

But again, a major concern is gigantic difference between BMW F3x manual and current conditions fresh air control button behaviour.

[HighlandPete]

Originally Posted by ybkbmw

Running a data logger is the most obvious first step but mine says they don't have it.

But again, a major concern is gigantic difference between BMW F3x manual and current conditions fresh air control button behaviour.

BMW UK provided and fitted/removed the data logger, in my case.

The manual won't be explaining every particular button pushing reaction, as you initially change, flip through the setup.

The feature/function description is clear for specific running settings. But repeatedly playing with buttons can 'upset' the system. Often requires time to stabilise, or prioritise and/or eliminate conflicts first, like dealing with humidity.

In my current car, cycling through AUC/outside air, doesn't always follow what I'd expect. Sometimes it immediately changes flap positions, air flows and fan speeds, other times it appears to do nothing. System is working correctly in use.

[deviantspeed]

Originally Posted by ybkbmw

Running a data logger is the most obvious first step but mine says they don't have it.

But again, a major concern is gigantic difference between BMW F3x manual and current conditions fresh air control button behaviour.

If your BMW Dealer does not have a diag tool, they should not be a BMW Dealer.

Go find another one that has the required tools.


PS, you should report the BMW Dealer that can not do diagnostics.

[EvenKeel]

Op my system does what you're describing.

[agentorange]

The OP seems to firmly believe that the air outside his/her vehicle is drier than inside when there are people on board. The location "Salem" is ambiguous, but the two most notable are in Massachusetts and Oregon neither of which is know for their dry climate, soooo I dunno about the dry air being outside.

As for the A/C setting taking over regardless of the recirc setting, I believe that is largely true with mine as far as I can tell. I'm not too fussed, because when it is 104°F/40°C or more with suspended dust and traffic products, the last thing I need is outside air.

I do agree with the OP that you can hear when a car is in recirc compared to pulling outside air when you have the fan up high. ICan hear it on my F30, ML350 and it was REALLY obvious on the Xterra I used to own. I must assume that those who claim they cannot hear it are at least tone deaf.

[ggrcrash]

Question, perhaps this was answered elsewhere, but why would you even want to operate the AC system with fresh air on? This is akin to operating the AC system with the window open? Correct me if I'm wrong about that. Wouldn't doing that, just freeze up your condenser? Again correct me if I'm wrong about that one too. WTH?

[bimmer456]

Originally Posted by 1KWIKBMR

Auto/manual/open (no LEDs) for the fresh air vent.

It should really be R for recirculate rather than M for manual.

[t2t]

Originally Posted by ybkbmw

Running a data logger is the most obvious first step but mine says they don't have it.

But again, a major concern is gigantic difference between BMW F3x manual and current conditions fresh air control button behaviour.

ybkbmw Hi, did you ever figure out what was causing this behavior or if it is normal? I am seeing a similar issue on my 2022 g20. thanks

[thejeremyman9]

Hah i just read through this entire thread. I find it amusing because my car actually does the same thing as OP and I was never able to figure out why, assumed it was just a BMW thing. I do think its annoying when turning the AC on forces the car into recirculate mode if there is enough of a difference between the setpoint temperature and outside ambient temp (i.e., its hot outside and you are setting it to a low temperature inside). It doesn't make sense IMO when there is a separate button for recirculate settings and that effectively does nothing in this situation.

[JeffHou73]

This is the first I have seen this entire string but find it very interesting. I have a 2020 M340i and last year, I began having some issues with either mold or moisture building in the evaporator - just getting some musty air...but still cooling well. All that seemed to resolved itself over time. HOWEVER, along the way, I observed the exact problem you have outlined in the initial post of this thread. The system does ignore the fresh/recirc/auto button ANYTIME the A/C is on, in which case it is always in recirculate mode. Aside from the sound of the air never changing, when switching modes (with A/C on), you can actually see the primary flap underneath cover the secondary battery located in the engine compartment, in front of the passenger. In fact you actually see the incoming side of the cabin filter. The ONLY way to get that flap to open is to turn off the A/C and then set the mode to "fresh air". You definitely hear and feel the air speed slow down in the cabin. If you then switch it to "recirculate", the A/C comes on automatically (which is crazy) and the air speed speeds up. THEN, if you turn off the A/C and don't touch the mode button for the air, you can have recirculating air without the A/C on (although I would never recommend it). However, you cannot have the A/C on in fresh air no matter what you try.

I actually met with a factory engineer about this here in Houston and, in effect, won a bet. he assured me the flap would be open if I put the switch in fresh air mode with the a/c on. When he saw that did not occur, he shook his head and was in somewhat disbelief. The on thing he did tell me but could not confirm was that there is more than one flap and just because we couldn't see any other flaps, he tried to assume there was still at least one flap keeping fresh air moving when the A/C was on. While this may be true, I'm convinced I will never know this for sure. The fact the air speed doesn't change convinces me, there is ni fresh air being coming thru the cabin filter when the A/C is on...which is 98% of the time in Houston. This explains why, after 3 years, my cabin filter still looked like new. Although, I did replace it anyway for good measure. Anyhnow, just wanted to share my story. The originator of this thread raised some good points and good he persisted in getting some feedback. BMW does do some crazy things and it is amazing how few people - including technicians and field representatives still do not understand about these cars!

Thanks for listening and look forward to any feedback or input any of you may have.

[thejeremyman9]

Originally Posted by JeffHou73

This is the first I have seen this entire string but find it very interesting. I have a 2020 M340i and last year, I began having some issues with either mold or moisture building in the evaporator - just getting some musty air...but still cooling well. All that seemed to resolved itself over time. HOWEVER, along the way, I observed the exact problem you have outlined in the initial post of this thread. The system does ignore the fresh/recirc/auto button ANYTIME the A/C is on, in which case it is always in recirculate mode. Aside from the sound of the air never changing, when switching modes (with A/C on), you can actually see the primary flap underneath cover the secondary battery located in the engine compartment, in front of the passenger. In fact you actually see the incoming side of the cabin filter. The ONLY way to get that flap to open is to turn off the A/C and then set the mode to "fresh air". You definitely hear and feel the air speed slow down in the cabin. If you then switch it to "recirculate", the A/C comes on automatically (which is crazy) and the air speed speeds up. THEN, if you turn off the A/C and don't touch the mode button for the air, you can have recirculating air without the A/C on (although I would never recommend it). However, you cannot have the A/C on in fresh air no matter what you try.

I actually met with a factory engineer about this here in Houston and, in effect, won a bet. he assured me the flap would be open if I put the switch in fresh air mode with the a/c on. When he saw that did not occur, he shook his head and was in somewhat disbelief. The on thing he did tell me but could not confirm was that there is more than one flap and just because we couldn't see any other flaps, he tried to assume there was still at least one flap keeping fresh air moving when the A/C was on. While this may be true, I'm convinced I will never know this for sure. The fact the air speed doesn't change convinces me, there is ni fresh air being coming thru the cabin filter when the A/C is on...which is 98% of the time in Houston. This explains why, after 3 years, my cabin filter still looked like new. Although, I did replace it anyway for good measure. Anyhnow, just wanted to share my story. The originator of this thread raised some good points and good he persisted in getting some feedback. BMW does do some crazy things and it is amazing how few people - including technicians and field representatives still do not understand about these cars!

Thanks for listening and look forward to any feedback or input any of you may have.

What if you raise the set point temperature? In my case, turning the AC on does not ALWAYS put the car into recirculate. There has to be a big enough temperature difference between current temp and setpoint temp as I mentioned in my post above.

So let's say in your case its 70F outside. If you set the AC to 60F it will probably go into recirc. However if you continue raising the setpoint temp higher and higher will it eventually go into fresh air mode? In my case, it will. But if it starts to get hotter outside (or perhaps in the car), it will then kick itself back into recirc automatically regardless of the settings for that.

[22Black]

Originally Posted by JeffHou73

This is the first I have seen this entire string but find it very interesting. I have a 2020 M340i and last year, I began having some issues with either mold or moisture building in the evaporator - just getting some musty air...but still cooling well. All that seemed to resolved itself over time. HOWEVER, along the way, I observed the exact problem you have outlined in the initial post of this thread. The system does ignore the fresh/recirc/auto button ANYTIME the A/C is on, in which case it is always in recirculate mode. Aside from the sound of the air never changing, when switching modes (with A/C on), you can actually see the primary flap underneath cover the secondary battery located in the engine compartment, in front of the passenger. In fact you actually see the incoming side of the cabin filter. The ONLY way to get that flap to open is to turn off the A/C and then set the mode to "fresh air". You definitely hear and feel the air speed slow down in the cabin. If you then switch it to "recirculate", the A/C comes on automatically (which is crazy) and the air speed speeds up. THEN, if you turn off the A/C and don't touch the mode button for the air, you can have recirculating air without the A/C on (although I would never recommend it). However, you cannot have the A/C on in fresh air no matter what you try.

I actually met with a factory engineer about this here in Houston and, in effect, won a bet. he assured me the flap would be open if I put the switch in fresh air mode with the a/c on. When he saw that did not occur, he shook his head and was in somewhat disbelief. The on thing he did tell me but could not confirm was that there is more than one flap and just because we couldn't see any other flaps, he tried to assume there was still at least one flap keeping fresh air moving when the A/C was on. While this may be true, I'm convinced I will never know this for sure. The fact the air speed doesn't change convinces me, there is ni fresh air being coming thru the cabin filter when the A/C is on...which is 98% of the time in Houston. This explains why, after 3 years, my cabin filter still looked like new. Although, I did replace it anyway for good measure. Anyhnow, just wanted to share my story. The originator of this thread raised some good points and good he persisted in getting some feedback. BMW does do some crazy things and it is amazing how few people - including technicians and field representatives still do not understand about these cars!

Thanks for listening and look forward to any feedback or input any of you may have.

Hey, did you ever find a solution to this? I started a thread here about this on the G20 forum. I find this to be really concerning!

Link to my thread:
https://g20.bimmerpost.com/forums/sh...3#post30269353

[Chris_Socal]

It was interesting reading this...albeit 2 years later. This issue has bugged me since the day I bought my car new in 2013. I owned an 08 335 before this one and the behavior is certainly different. The minute I got my 13 I noticed it had strange AC tendencies. The first thing I noticed, and hated, is that the AC will run after starting the car, even when the AC is turned off. SOMETIMES.
I hate AC.
What bugs me is the general attitude that BMW has a reason and/or it makes sense. I live in southern CA (NOT LA haters), I live where humidity is noticeable on the days it rains which can be counted using your fingers. Sometimes I start the car in the morning and it's dry as paper outside but the AC will turn on, I turn the heat up, the AC runs for about 5 minutes then shuts off and suddenly I'm heating the car so I have to turn the temp down. See, I have to fidget with the knobs so why not let me choose? The next day it might be damp (to us) but the AC doesn't run automatically so I manually turn it on.
Have I mentioned that I hate AC?
I only use it when it's really necessary so when the car turns AC on when it's 55 degrees in the morning I hate my car. See the relationship between loving your car "because it's a BMW" and living with it and wishing you hadn't. I know some other car vendors do this too but that doesn't make them smart just because they do it too. And saying it is performing as designed is a cheap answer. I was told that for 6 months when my car had a rattle after buying it. I learned to hate that answer.
Why does BMW think they are smarter than those of us who wish to press the button when we want AC? I never had issues with AC on a car until they started overriding my choice. Think about it, we are talking about a car company that never wanted to design cup holders into the car, they thought the little coffee cup holder in the armrest was sufficient even though the dealers told them for 10 years that they needed cup holders. I don't consider anything they do "Smart".
Intelligent maybe, but I never presume Smart.
Point being, we do NOT need the AC to run in order to prevent fogging of windows. I have 4 cars and 2 of them don't have AC. I can't remember the last time I had fogged up windows. Maybe when the dewpoint reached total saturation one rainy day in 2010 LOL.
Like the original post, my '13 335 recirculates the air when the AC comes on. I hate that even more than the AC running. I haven't connected B-link to see if the code says it is recirculating but you can hear the flap close and the fan is audibly louder. Plus you can feel the airflow differential. This is all confirmed if you press the recirc button there there is no difference like there is when the AC is off (on those moments the car lets you turn the AC off).
I read that some models can be code changed to not auto-recirculate when AC is on so that verifies that BMW is coding it to recirculate when AC is on, on some models. Mine only has the option to save the last setting which doesn't make sense because it's always recirculating.
You know, I never had issues with AC when I drove a car with a dumb air conditioner, they worked just great and I honestly never gave AC any thought. Windows fogging up on one of 10 rainy days? Turn the AC on. Is it hot? Turn on the AC. What's even more novel is if you moved the dial to Fresh your got fresh air.
The problem is BMW got too pretty. They aren't driving machines anymore, they are trying to compete with luxury cars so they are heavy and have too much automation.
Do I love the way my BMW drives? Yes
Do I love their finish materials? Yes
Do they have attributes that are not smart? Yes

"BMW, You hate to love it".

[Chris_Socal]

Originally Posted by ggrcrash

Question, perhaps this was answered elsewhere, but why would you even want to operate the AC system with fresh air on? This is akin to operating the AC system with the window open? Correct me if I'm wrong about that. Wouldn't doing that, just freeze up your condenser? Again correct me if I'm wrong about that one too. WTH?

Back in 1972 (or so) GM created a setting called bi-level. It ran the AC up top but let warm air in the feet based on your heat setting. This was great in climates where we have sun most of the year but the air temp isn't hot. Our cars get warm from the greenhouse effect but it isn't "hot" outside. If we can see the sun, it warms the car. I never used Recirculate on my AC in a car until BMW forced me to. The only time I switched to Recirculate is when it was really hot and for the first few minutes the car was cooling down. In CA we often drive with sunroofs propped up in the back with fresh/cool air flowing through. The goal isn't to cool the car (like a house) and hope the compressor turns off soon.
BMW allegedly uses a variable compressor so why not let us choose when to turn it on. During the Spring and Fall fresh AC Air is refreshing but recirculated air is picked up down by your feet...is that what you want coming out of your vents?