'15 Z3. White TT with 20V at fuse panel

[406Z3]

Just bought a '15 Z3 with under 40 hours on it. First time out this weekend and my display is white, nothing else. So I checked voltage at fuse panel and it has 20 volts going in. I disconnected both batteries and one has 19.4 and the other has 18.3. Any thoughts? Anyone have a battery wiring diagram so I can verify this is wired correctly?

Thanks all.

[freeheel4life]

That is ridiculous. typically only see voltages like that if a voltage regulator fails and causes alternator to full field, alternator can also put out voltage that high if it has lost its connection to batteries and full fields, but you would only see that while running and checking voltage at B+ of alternator and not at batteries so doubt that is problem. If batteries are disconnected and you are getting 18 and 19v something is wrong. Is your meter a nice one or a cheap radio shack/craftsman?? Only other way I could see getting voltages like that is if they got wired up in series instead of parallel and you have a very low state of charge. Regardless you have some funky stuff going on if that is truly your OCV

[406Z3]

Meter was garbage. Super frustrating. So I'm good with voltage. Have 12.5. Everything seems to be charging just fine. Still have a white screen. I guess the dealer had replaced this screen a year ago.