BMW 6-Series Battery Warning Signs: What To Check Now

Hey there! I had very similar symptoms with my 2013 BMW 5 series last winter. Started with dim lights and slow cranking, then got worse. Initially thought it was just the battery, but turned out the alternator was failing, which then damaged the battery because it wasn't charging properly. The error code in my case was related to the electrical system. Had to get both the alternator and battery replaced because waiting too long with the faulty alternator ended up killing the battery completely. It was definitely a serious issue that needed immediate attention since it could've left me stranded anywhere. Based on your symptoms, sounds exactly like what I experienced. These electrical issues tend to cascade, one problem leads to another. My advice would be to get it checked soon, preferably at a BMW specialist who knows these systems well. Not something you want to ignore or it'll likely get worse. Good luck with the fix.

Thanks for sharing your experience! That's really helpful since it sounds just like what I'm dealing with. I'm curious, do you remember roughly how much you ended up paying for the alternator and battery replacement? Also, have you had any other electrical issues pop up since getting it fixed? Just want to know what I might be in for.

Hey again! Happy to give you an update! After seeing a specialist, everything's running perfectly now. The alternator was indeed the culprit, just like I mentioned before. The total came to around 850€ for the alternator itself and labor. The really good news? The battery didn't need replacing after all, turns out it wasn't damaged and just needed a proper charge once the alternator was working correctly. So that saved me some cash! Since getting it fixed last winter, I haven't had a single electrical problem. The car starts right up every time, no more dim lights, and all systems are working great. The mechanic explained that catching it when we did probably prevented more expensive issues down the line. Here's a tip: if you're planning to get yours fixed, ask them to check the serpentine belt while they're at it, it's right there by the alternator and often needs attention around the same time. Better to check everything while they're in that area. Let me know how it goes with yours!

Thanks so much for all the details! I actually bit the bullet and took it to a BMW specialist yesterday. You were spot on, it was the alternator! Got it replaced and they did check the serpentine belt too (good call on that tip). The whole thing cost me about 900€, which honestly wasn't as bad as I feared. The mechanic was really thorough and showed me exactly what was wrong with the old alternator. No wonder the car was acting up! They were able to save my battery too, just like in your case. Drove it home today and what a difference! The engine turns over instantly, all the lights are bright and steady, and that annoying error code is gone. Such a relief to have it sorted. Really appreciate you sharing your experience, it gave me the push I needed to get it checked out before things got worse. Case closed on this one! Thanks again for all your help.