BMW Z3 Electrical Nightmare: Dashboard Warning Light Chaos

Hey there! I have some experience working on BMWs and dealt with a similar issue on my 2003 BMW Z4 last year. When my car showed those electrical gremlins and lit up like yours, it turned out to be a dying battery that was causing havoc with the electrical system. Had the same symptoms, sluggish starts, unusual warning lights, and voltage-related fault codes. Took it to my regular workshop, and they confirmed the battery was shot after testing it. They also checked the alternator to be safe, but it was fine. The new battery install plus diagnostic work came to around 290 Euro, but it solved all those electrical issues completely. Quick question, have you noticed any other symptoms like flickering lights or power windows acting up? Also, when was the last time you replaced the battery? This info would help compare situations better. If you want to be thorough, might be worth having them check your alternator too, just to rule it out. Better safe than sorry with electrical problems on these cars.

Thanks for sharing your experience! Mine's at 97295 KM and just had a service last month, but this issue started right after. You might be onto something with the battery suggestion. Actually noticed the power windows getting slower recently and the radio sometimes resets itself. Been suspecting something's up with the electrical system but wasn't sure where to start. Think I'll get both the battery and alternator checked out. Better to fix it now than get stranded somewhere. These old Z3s are great cars but they definitely need proper care, especially with the electronics. Did you use OEM parts for your repair? Just wondering if aftermarket batteries work just as well on these models.

Hey again! Yeah, when you mentioned those additional symptoms, especially the slow power windows and radio resets, it really sounds identical to what I experienced with my Z4. For my repair, I actually went with a high-quality aftermarket battery (Varta) instead of the OEM BMW one. It's been working perfectly for over a year now and saved me quite a bit of money. The key is making sure it matches the correct specifications for our cars, same amp rating and size. Just so you know, after my experience, I learned these symptoms often show up soon after a service because all that diagnostic computer hook-up can sometimes be the final straw for an already weak battery. Makes total sense that yours started acting up right after the service. One thing I forgot to mention in my first reply, before replacing my battery, I tried jumping the car a few times, but the problems would come right back. That's when I knew it wasn't just a simple discharge issue. Trust me, getting this sorted will save you a lot of headaches. These Z-series BMWs are really sensitive to voltage issues. Would love to hear how it turns out after you get it checked!

Thanks so much for all the detailed info! Really helpful to know about your experience with the Varta battery, definitely going to look into that option. You've saved me some cash there! What you said about the diagnostic hook-up during service being the final straw makes total sense. I've booked it in at my mechanic's for tomorrow morning. Going to have them check both the battery and alternator, just to be thorough. Funny you mentioned the jumping attempts, I tried that too last weekend and had the exact same experience. Problems came right back after a short drive. At least I know I'm on the right track now! I'll update you once it's fixed. Really appreciate you taking the time to share your experience. These old BMWs definitely keep us on our toes, but they're worth the extra care!