E36 M3 Air Conditioning Issues - Please Help!

[rowley7]

I'm curious if anyone else has had this same problem or knows how to fix it... My A/C (97 M3) has a mind of its own, and it's really frustrating at times, especially on hot days!

It will be working fine, then all of the sudden, my climate control LCD display just goes black, and the A/C stops blowing. Also, the fan stops working, so there is literally no air coming out of the vents. The LED light for the A/C button and the LED for the location that I want to blow the air (head, foot, both) are still on, but there is no air! Sometimes it stops working, but the climate control display goes completely black, including the two LED lights mentioned above. It also feels like the A/C compressor is still running b/c I can feel the extra strain on the engine, just like when it's all working fine and the A/C turns on.

My passengers have also noted that when I turn a corner pretty fast, they get some water dripping on their feet, which I assume is from a condensation drain or something that is not working properly??

The A/C display LCD will also sometimes get really dim, and the blower will stop, but if I'm moving, really cold air (almost freezing) will still come out of the vents, but no air will come out when I stop at a light. While I'm at the light (and the display is really dim still), it almost sounds like ice crystals are forming in the dash.

In any of the scenarios mentioned above, it can just turn back on and work properly, and for no apparent reason. In the last paragraph, when it does come back on, the air will be extremely cold for a minute when it comes back out and there is a steam-like smoke that comes out of the vents, just like when you open a freezer.

Any help or insight on this issue would be very much appreciated!

[fun2drive]

You have the classic failure of the HVAC system do to a cracked PCB board. There are many places that repair this and many DIYs that show how to replace a capacitor that is causing this. Actually reflowing the solder around that cap is all that is needed.

Your other problem you need to check your drains which are rubber looking hosed with a 90 degree turn out of the firewall. Thin wall rubber about 2 inches or so right behind the valve cover...

[rowley7]

Thanks for the info...it is much appreciated! For anyone else looking for more info on this problem, here is a link to the fix (hopefully, haven't tried it yet).

http://www.macadamizer.com/bmwfix.html

[rowley7]

Status update...I followed the instructions listed on the above website and 2 days later, my HVAC has been working flawlessly and is still nice and cold! I wish I would've found that info at the beginning of the summer! Oh well.

For the capacitor (as per the article), I used a 35 volt tantalum 1.0 microfarad and so far so good.