BMW 5 Series Heating System Failure: Solutions & Fixes

Hey there! I've got some experience working on cars and had a similar issue with my 2012 BMW 3 Series (I also own a BMW 1 Series). Last winter, my heating system acted up too. Got those annoying error messages and nothing worked properly. Took it to the workshop and turns out the battery was heavily discharged, which was messing with all the electrical systems, including the heating. They had to replace the battery and recalibrate some systems. Whole thing cost me 290 Euro, but it fixed the problem completely. Before you go to a workshop though, could you share what specific error messages you're getting? Also, have you noticed any other electrical issues, like dim lights or slow starter? This info would help figure out if you're dealing with the same problem I had.

Thanks for sharing your experience! My situation seems a bit different though, just had my BMW serviced at 81732 KM and they checked the battery, which was fine. Actually, after reading your reply, I remembered that before the heating completely failed, I noticed some weird clicking sounds from the dashboard area when turning the heat on. Definitely don't have any issues with lights or starting the car. The error message I'm getting is specifically about the heating system control unit. Wonder if it could be a faulty actuator or something with the control module itself?

Oh, those clicking sounds from the dashboard definitely ring a bell! After you mentioned that, I'm pretty sure we're dealing with different issues here. In my 3 Series, when I had those clicking sounds before complete failure, it turned out to be the heating control module that was failing. Unlike the battery issue I mentioned before, this was more specific to the heating system itself. When I took it back to the shop, they diagnosed a faulty actuator in the control module. The clicking was basically the actuator trying but failing to work properly. In my case, they ended up replacing the entire heating control module because individual parts weren't available. Cost me around 400 Euro, but at least it solved the problem completely. Since you're getting specific heating system control unit errors and hearing those clicks, I'd bet you're facing the same issue. When they replace the module, make sure they recalibrate the system properly, learned that the hard way when I had to take it back because they skipped that step the first time. Just a heads up though, if you're planning to get it fixed, do it sooner rather than later. I waited too long and ended up with completely fogged windows during some really cold days. Not fun at all!

Thanks a lot for the detailed explanation! That actually makes a lot of sense about the clicking and the control module. I really appreciate you mentioning the recalibration part, that's exactly the kind of insider info I needed. I'll definitely get it checked out right away, especially since winter's coming up. Don't want to end up with those fogged windows you mentioned! Just made an appointment with my regular mechanic for next week. Do you mind if I message you again after the repair to let you know if it was the same issue? Really appreciate your help with this!