Parked01

Hi,

strange thing has happened, went to put the AC on today as it’s bloody hot here, all I was getting was a noise that sounds like a vent is closed within the system - whooshing air but nothing coming out of any vent, it’s only when the AC is on though - normal fans work fine.

does anyone know if the AC system pushes the air through a different system or if there is a join somewhere just behind the dash that I can’t see on drawings and the like? Wondering if a flap has become wedged or something back there but wouldn’t know what to look for without some indication of what it looks like!

thanks

seanjordan20

Starting to be a common issue with the F series vehicles and G series is starting to be affected also. Dealership will say it's normal operation but it's has something to do with the software. Some solve it by replacing the battery as it is on it way out. Some are saying it starts to have issues between the 80-100 degree range only. Most restarting the car and it starts back working.

I'm currently having the same issue with my F16. It corrects itself with a restart but I believe it's a software issue. Do you know what I-step your IHKA is on currently. Before i drive mine again I'm going to do an update on my IHKA to see if it corrects the issue. I am assuming the climate door is not opening because the rear has no issue but there is no error in the system for a bad blend door.

Parked01

Well that’s the thing so no air is coming out of the vents at all which is why I’m thinking it’s a vent or similar that isn’t opening, no AC and the cool and hot air all work no problem, just when I switch AC on

seanjordan20

That's the exact issue I'm responding to. Air full blast but nothing coming out. Door is not being flipped.

Parked01

Ahh sorry, thought you were speaking more about the AC not being all that cold! So the battery isn’t an issue I was pulling a decent voltage when the garage tested it a few weeks ago (unrelated issue) so what’s the general consensus is it a software or mechanical issue typically?

if it’s technical is there a specific valve/flap I can look at?

seanjordan20

I'm going to test the theory of it being a software issue by updating my IHKA. A number of people of taken it to the dealership and SA came back to say it's normal operation. I read one thread where someone actually got the dealership to replace the IHKA and climate door bu Tarik has the same issue. Since the G series is having the same issue I've been looking at the issues being resolved with each i-step and none this far has addressed an IHKA issue. I just updated my ISTA and haven't looked at what the new istep has addressed but I will be updating it to it. I've had luck in the past with just an update fixing an issue with CarPlay so I'm hoping the same will be with this issue.

Parked01

Anything is worth a try! I did try and read error codes off it to see if anything came up - the only message stored is terminal 15n intermittent signal but I have absolutely no idea what that’s about - not sure if it may have any impact to HVAC or not (electrics are not my strong point)

seanjordan20

Terminal 15 is used to signal the status "Ignition ON/Ignition OFF" rather than as a power
supply. That applies, for instance, in the case of the digital motor electronics (DME), the
footwell module (FRM) and BMW Night Vision.

Terminal 15 N (Overrun) is used for control units and electrical loads operating at status
"Ignition ON" when the vehicle is being driven. That applies, for instance, to the lane
departure warning (SWW), short range radar (SRR) and Night Vision

You may need to check the relay for Terminal 15N or look at your ISM, could be faulty

Parked01

Ok, must admit that I will have to do some research on those before attempting anything! I suppose long and short of that issue is it’s unrelated to the AC thing - just another thing to look into!