Author Topic: 8.5 GTI - low 12V battery from new  (Read 760 times)

Offline Bellovese

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8.5 GTI - low 12V battery from new
« on: 24 April 2026, 17:35 »
Hi

Been driving my new 8.5 GTI for more than a month (1300 km) and a few seconds with the ignition on are enough to get the yellow "12V battery low, start engine" warning.
It's been happening from the very beginning in the showroom. Salesman put in on an external supply for the duration of the handover, said they now all do that when they arrive and VW said it's normal.

I'm coming from a 2020 Leon that hated low voltage but even that one let me navigate in the infotainment for a long while without any warning.

I've now done multiple 2hr+ trips and it's still doing it. Anyone else having this?

Thanks

Offline valentino

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Re: 8.5 GTI - low 12V battery from new
« Reply #1 on: 26 April 2026, 10:04 »
If mine has the ignition on without the engine running, and i am scrolling through the infotainment centre, it does say switch on engine as its discharging the battery.I think thats normal

Offline candywhite12

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Re: 8.5 GTI - low 12V battery from new
« Reply #2 on: 30 April 2026, 16:42 »
same here.  discharges if you are using the infotainment but engine is not running, i wouldn't worry too much about it as it seems to charge properly once you turn ignition on, all notifications then go away
Current: GTI 8.5, Moonstone Gray, 5dr, Black Estorils 19''. pan, DCC
Wife's: mk8 TSI 1.5 RL, 5dr atlantic blue, DSG, Norfolk 17", pan s/r, leds
Son's: mk7.5 TSI 1.4 RL, 5dr tornado red, DSG, Singapore 17", pan s/r, leds
Before: mk6 GTI 5dr candy white, DSG, Monza Shadow 18", s/r, bi-Xenons, DCC
Even before that: mk5 GT 5dr tornado red, manual, s/r

Offline JoeGTI

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Re: 8.5 GTI - low 12V battery from new
« Reply #3 on: 30 April 2026, 16:51 »
These cars don't seem to like being left idle and unlocked. Even if the infotainment system is switched off.

I've noticed it a few times, where say I've been washing the car (car unlocked with key left inside it). Next time I drive it, post-wash, the infotainment system takes a while to get going, that whole "loading settings" malarkey. And I've had the low voltage error ping on the dash too, typically if sitting in the car with the radio on, even only for a few minutes.

It always resolves itself once you've driven it a bit and its "charged up" again I guess.
MK8.5 GTI Clubsport. Moonstone grey. Queenstown 19’s. DCC. Harmon Kardon sound. Pano roof.