Ventilation always blows warm air

[2.5tdi]

It is just flap motor, I dont know any other terms. You have picture of mine on 1 page of this thread.
On ista you can check flap position from 0-100%, that is what i would check.
Yes it is pretty difficult to access it (mostly because car is so small) and it is behind other two motors (footwell and defrost i think). You have to remove glovebox and plastic beneath it then you can access it.

It is number 1 motor on photo.

 

[NaweedM]

Hmm, also out of curiosity, is this responsible for the mixing flap by any chance? was set to not active, i later activated it 2 months ago and left it that way. just deactivated it right now to see if changing it was the cause of all of this.



regarding access to the motor, i'll try and check some manuals and youtube, not looking forward to this task if it requires a lot coming off

 

[2.5tdi]

I don’t think it is related.
It does not require a lot coming off, just glovebox and plastic beneath. It is difficult because of space, it helps if you are not tall.
Mine replacement motor should arrive this week, i will take some photos of process.

 

[NaweedM]

Mine replacement motor should arrive this week, i will take some photos of process.

I would be very grateful for this.

So from what i can gather here, the Mixing motor % (From my 1st picture) should be adjusting depending on the temperature selection, correct?
For others following this thread, on ISTA, it is labelled as "blending flap"

 

[NaweedM]

After some tinkering around on INPA, it seems i cannot control the mixed air flap servo, so thats a telltale sign. Anyone with working flaps that can try this? i also noticed another strange thing. When trying to alter the fresh air flap, it just went straight to 0%, so not sure if thats a servo we can freely adjust

 

[2.5tdi]

I think fresh air flap is supposed to work like that.

I got motor yesterday but it is faulty (shows short to ground fault), then i installed back my old motor and it now started to work like it is supposed to (mixed air is changing when i change temperature setting). I have no idea why…

Here are some photos. It’s not necessary to remove plastic under glovebox, i somehow forgot and was wrong in last post.

After you pry out motor you have to wiggle it out with hand, install it in reverse process. You have to have it set in middle position, you can just turn motor with hand slowly.

 

[NaweedM]

THanks for the pictures! i will have a look. i'm also hoping that it just needs a good clean to work again. I assumed i didn't need air-conditioning as the outside temps are dropping however, with the mix flap not working, the car constantly fogs up...

 

[2.5tdi]

Mine is also fogging. I hope this fix will help

 

[NaweedM]

So I decided to inspect the servo. Wow was it annoying to fit back inside. Removal was alright. The mixture servo works good. Decided to switch on the ignition and turn on the HVAC system. Saw the servo move. Playing around with the temp setting didn't do anything other than that initial move. I think I need to perform an AC service with the freon gas.

When fitting it back, I had to rotate the servo to its original position and damn was it hard to move

 

[2.5tdi]

Yes, it’s real pita. I’m glad you did it.

So it moves step by step when you change temperature?
But in previous post you could not move (via inpa) mixed air flap?

 

[NaweedM]

Yes, it’s real pita. I’m glad you did it.

So it moves step by step when you change temperature?
But in previous post you could not move (via inpa) mixed air flap?

Inpa was acting a bit weird. because when i tried to move the footwell flap, no matter what percentage i set, it just defaults to zero and the flap fully closes. so i would guess that is why i cannot control the blend servo. As for the step by step movements, it didnt do that when i was turning the temperature dial, it did move initially when i started it. I should have manually moved the flap to check for cool air but for now, im convinced i may need to refresh the freon gas.

 

[2.5tdi]

I’m still struggling to find a solution to my problem. I can’t find a used motor with the same part number, and new ones aren’t available. However, I’m not sure if replacing it is necessary since the old one seems to be spinning normally.

Does anyone have any suggestions on what I should do?

 

[NaweedM]

Resolved my issue by replacing the compressor. It had a strange bad bearing noise and turns out that was the root cause. you can test by turning on/off the frost button and notice if you hear a noise that sounds like a worn bearing

 

[2.5tdi]

The AC is working perfectly fine. However, when the AC is off and the temperature is set to the minimum, it should blow air at the same temperature as the outside air—but that’s not the case for me.

 

[scottyD]

Glad I found this thread when the same thing started happening to me yesterday - HVAC blows hot air even when temperature knob set to coldest, and ambient temperature outside is also cold (A/C also turned off).

INPA found this error code stored in the IHKA85 module (along with the Google translation):

• 35 Motor Temperaturmischklappe (motor temperature mixing flap)
  Kurzschluss gegen Masse (short circuit to ground)
  sporadischer Fehler (sporadic failure)
  Errorcode: 23 82 0D 58 16 09 29 00 00 03 B2

Started searching for a replacement part number - realOEM (along with other sources, including your photos posted earlier in this thread) tells me it should be 64116936709

Here's the fun part - everywhere I search online I only see "discontinued" and it's simply not available...
2.5tdi, sounds like you are seeing the same thing?

Reached out to my local dealership as well as a few online parts places to ask if they have any other details they can provide. Hoping that BMW has an alternate part number that can be bought instead.

Also tried searching for the Denso 113930-0311 part number, but no luck.

Never had this happen before in all my years (replacement part simply unavailable).

 

[2.5tdi]

I finally managed to find a used one in Sweden. Expensive, but at least I got it. Now I’m waiting to reassemble the lower end of the engine before testing it.

Yeah, it’s nearly impossible to find. There are a few in the U.S., but I wasn’t willing to pay the import taxes.

You could try unplugging it to see if the fault code changes, that might help rule out a wiring issue.

 

[scottyD]

Just curious, where in the U.S. were you finding 64116936709 available? I couldn't find it anywhere. I'm also ignoring the shady looking ones available on Amazon.

RealOEM says 64116936709 (newer part, but "no longer available" or "discontinued" everywhere I looked) superseded 64116917065 (older part, also generally not available). Luckily (I think), I was able to find the older part today online and bought it almost immediately.

I haven't taken the failed one out yet... (I'm assuming it's failed or not far off based on the INPA code). I'll wait for the new one to arrive before digging into the dash board. Thanks a lot for your photos, that helped understand the process. Getting access doesn't seem too difficult - I think BMW's repair instructions say to remove the radio and the center air grill, but it doesn't look like you had to do that, right?

 

[2.5tdi]

I managed to find one on eBay, hope you can get one too.

I didn’t remove the radio and center air grille. It’s possible to get it in, but it’s very tricky. There’s barely enough space for one hand and a screwdriver.

 

[2.5tdi]

New/used motor for temperature flap, same problem.
I have no ideas left…

 

[NaweedM]

Did you check the flaps on inpa? For me i thought it was my mix flap but i saw on inpa it worked fine when going from hot to cold without auto climate control.

In the end it was my compressor that had to be replaced. When i turn on and off the frost button via inpa close to the engine bay, i heard a bad rattling noise