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981 Battery Voltage ups and downs

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Just thought I'd post an update on my 2014 981S now with a bit over 82,000 km = 51000 mi. on it.

Last Fall, the voltage, while driving started to climb on a 200 mile drive and eventually sat at 14.9 - 15.0 V under most driving conditions for the next roughly 600 km (400 mi) which included the winter hibernation with a battery maintainer attached.

This month when I got the car out, I had the same readings on the first drive of about 60 mi. Then last weekend, we took a drive to Niagara On The Lake. Shortly into the drive, the Voltage gauge was all over the map for a few minutes, then settled in and gradually started dropping down to 13.8 V. Ever since then (about 300 km = 180 mi.), every time I've driven it, the voltage has been between 13.8 and 14.0 V, except when I put it into Sports mode. So it seems to be back to "normal".

Makes me wonder if the battery is run through some type of "super charge" mode around the 50,000 mi. or 6 years of use.
Yes, my car's voltage has had fluctuations in the past, maybe three years ago, which might've been around 50 thousand miles. The dealer assured me it was of no consequence then, and I haven't taken notice of readings above the high fourteens in quite some time. Must be that these cars have some form of AI. winking smiley
My early 2013 has similar symptoms.

I still get close to 15v shortly after start up, but it drops to 13.8 within 5-10 minutes or so. I normally drive not using sport or sport+ unless I drive aggressively and notice that putting it in sport bumps the voltage up immediately.

13 Boxster, Racing Yellow, PDK, SC in yellow, 20" Carrera platinum wheels, sport steering wheel, yellow seat belts, yellow roll bars, 14 way power seats, PDL, sports tailpipe
Just to add one more data point, the 2014 Boxster (Base model) that I got about a month ago will be at around 13.1-13.3 V at start-up, climb to around 14.8-15 V at highway speeds, and drop down to 13.7-14 V when I get back down to normal city speeds. So, all these fluctuations appear to be "normal".
Bouncing around a bit the first 10-15 miles then settling down to around 14v.
It makes sense for a short period of time. If the car has been sitting a few days, it's taking a bit of time to bring the battery back up to a full charge. Mine seems to have settled into that pattern too.

The difference was, for that roughly 400 mi. stretch, it constantly ran at 15V even on 60 - 100 mi. drives.
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