Macan's Mystery Voltage: Battery or Alternator Drama?

Hey there! I had very similar issues with my 2019 Cayenne Diesel (also Porsche) last winter. The symptoms were identical, weak starts, flickering lights, and general electrical weirdness. Took it to my Porsche specialist, and it turned out to be more than just a battery issue. The alternator was overcharging, which damaged the battery and affected the whole electrical system. They had to replace both the alternator and battery, plus recalibrate the voltage regulator. It was quite serious since overcharging can mess up other electrical components if left unchecked. The repair wasn't quick, had the car in the shop for 3 days while they did full electrical diagnostics to ensure no other components were affected. I can recommend my mechanic, they specialize in Porsche electrical systems and did a solid job sorting everything out. Haven't had any issues since then. Good luck with the fix!

Thanks for sharing your experience! That's super helpful as it sounds exactly like what I'm dealing with. Been a bit worried about the potential damage from these electrical issues. Mind if I ask how much the whole repair set you back? Also, has everything been running smoothly since the fix, or have you noticed any other quirks pop up? I'm trying to get a sense of what I might be in for with my Macan. Cheers!

Hey again! Great to hear back from you! You'll be relieved to know that after getting my Cayenne fixed, everything's been running perfectly smooth, no more electrical gremlins whatsoever! Just had it checked last week actually, and the overvoltage issue that was detected initially has been completely resolved. In my case, the total damage to my wallet was 290€ for fixing the defective battery. Much less than I initially feared, especially after hearing horror stories about Porsche repair costs! It was totally worth every penny though, the car starts like a dream now, and all those annoying flickering lights are history. Haven't noticed any new quirks or issues since the repair, which was about 6 months ago now. My advice would be to get it sorted sooner rather than later, these electrical issues can sometimes snowball if left unchecked. But based on what you're describing, it sounds pretty similar to what I dealt with, so hopefully it'll be a straightforward fix for you too! Let me know how it goes with your Macan!

Thanks so much for all the details! I finally bit the bullet and took my Macan to a Porsche specialist yesterday. You were right, it was definitely worth addressing sooner rather than later. Turns out my situation was pretty similar to yours, but I also needed some wiring work done. The whole thing cost me about 450€, which included a new battery and fixing some corroded wiring connections. A bit more than your repair, but still not as bad as I'd feared. Got the car back today, and what a difference! No more flickering lights, and it starts up like it's brand new. Really appreciate your help and advice on this. It's such a relief to have it sorted, and knowing someone else went through the same thing made me feel better about getting it fixed. The mechanic was great too, super transparent about everything they were doing. Thanks again for sharing your experience. It really helped me make the decision to get it checked out properly!