BMW M3 AC Failure: Essential DIY Diagnosis Guide

Thanks for sharing your experience! That's really helpful. I actually had similar symptoms with my AC module on my M3. Sorry to be nosy, but do you remember roughly how much you ended up paying for the whole repair? Also, has everything been working fine since then, or have you noticed any other issues pop up? I'm trying to get an idea of what I might be in for with this repair.

Really appreciate your detailed feedback! Just got back from the mechanic today, and I've got good news to share. Took your advice about finding someone who specializes in BMW systems, and it made all the difference. The guy I found was fantastic, super knowledgeable about these cars. Turns out it wasn't as bad as I feared. The main issue was a faulty relay and some worn-out wiring, plus they needed to recharge the AC system. Total bill came to around 400 €, way less than I was expecting after hearing about your repair costs! They got it all sorted in just a day. The AC is now working perfectly again, blowing nice and cold. No more warning lights on the dash either. Such a relief! Thanks again for steering me in the right direction with finding a good mechanic. Definitely learned my lesson about going to specialists for these kinds of issues. Going to keep this mechanic's contact for future reference. It's so hard to find someone trustworthy these days, but this experience has restored my faith a bit!