024.6is climate control

x5Alpine · #1 03-23-2014, 04:16 AM

So I'm sure many of you have seen my older posts about how my climate control turns itself off and on when I have the heater on. HVAC control unit replaced 3 times, FSR twice. My indy and I are at a complete loss. I'll have the heat running at 72 on any setting and after a while say 5-10 minutes it will shut itself off, then flicker on and off. If I turn the dial on the vents to the tree blue dots it will stabilize and work just fine. Please any help because it's seriously driving me insane

Sponsored Links

racingbmwm3 · #2 03-24-2014, 11:03 AM

Wow. From what I remember, the blending dial isn't tied in with the IHKA and shouldn't have any effect with the control unit. The other air flaps are controlled by the IHKA though. Is it possible one of the stepper motors for the air flaps could be failing/shorting to ground and overheating the IHKA? If they happen to be on the same power circuit as the blending flap, changing the state of the blending flap could alter the total current draw to something manageable by the control unit. How is the overall system air flow? Do you get about the same amount of air coming from all 3 levels if you adjust them one by one? If you have blockage somewhere, you could be overheating the FSR due to the control unit asking for higher and higher heat and not getting it?

Aftermarket radio or other non-factory parts in the vicinity?

x5Alpine · #3 03-24-2014, 12:31 PM

Yea, I was just about to explain how it appears some of the flaps especially the defrost cents don't seem to be opening properly and it sounds like it's being blocked by something. A few weeks ago the vents were working well for a short while then it was back to the same.

racingbmwm3 · #4 03-24-2014, 12:37 PM

At least you have a new lead to investigate.

x5Alpine · #5 03-24-2014, 01:13 PM

Does this mean the dashboard has to come out?

racingbmwm3 · #6 03-24-2014, 01:57 PM

I think you can access some of the stepper motors from the sides. You should be able to test them from the control unit wiring harness though. Then at least you could find out which one is blocked or defective. If there was something in there blocking, I think you do have to remove the dash to get it out of the airbox.

x5Alpine · #7 03-24-2014, 02:50 PM

How would you do that?

racingbmwm3 · #8 03-24-2014, 02:59 PM

you'll need the wiring diagram, should be in the Bentley. hmm...wait, those are on a bus. I guess you have to test each one individually at the motor.

x5Alpine · #9 03-24-2014, 09:30 PM

Thankyou so much for the help!

racingbmwm3 · #10 03-25-2014, 10:55 AM

You're welcome. Remember to post what you find!

Sponsored Links