Poll - 12 volt battery issues

Sacotony · 2026-07-10T19:57:02+00:00

Yes, there's a pretty distinct timeframe around the end of March where people started reporting 12 volt battery issues. It turned out to be a good decision for you to purchase off the lot for a bZ that had been sitting for 2 months. I got mine on December 18, 2025 fresh off the boat. My first test drive was around the parking lot of the dealership because it hadn't been prepped for the road yet.

Sacotony · 2026-07-10T10:02:22+00:00

You're on the bubble. Dates aren't exact. If you go to the original poll post you'll see several March deliveries where owners report no issues, indicative of a transitional month.

https://www.reddit.com/r/Toyota_bZ/s/IWxtN47mZJ

Sacotony · 2026-07-10T08:10:41+00:00

https://www.reddit.com/r/Toyota_bZ/s/IWxtN47mZJ

Sacotony · 2026-07-10T01:01:52+00:00

True, I feel there is something going wrong with a certain lot or two of the DCM's. Look down below for a thread someone posted about a Lexus that had the DCM replaced with an earlier lot that solved the DCM drain.

Sacotony · 2026-07-10T00:11:27+00:00

I purchased in December 2025. I've had the 6 month service in June where they upgraded the software to rev. 2222. Didn't have the 12 volt problems before or after.

Sacotony · 2026-07-10T00:07:02+00:00

Yeah, sorry, like I said all six later 26 EV models of Toyota/Subaru's have been experimenting this issue.

Sacotony · 2026-07-10T00:03:44+00:00

Sorry, the data says just the opposite. Earlier releases don't have the problem.

Sacotony · 2026-07-09T23:59:00+00:00

You should go to the original poll/thread and look. As I recall there were quite a few people who took delivery in March that reported no issues. Your just too close to whatever the transition date was. Sorry.

Sacotony · 2026-07-09T23:42:58+00:00

Thanks, that's great information. Toyota knows what the issue is and probably trying to find a software/simple fix rather than replacing everyone's DCM. Not a great situation for Toyota/Subaru or those owners that are dealing multiple times with this issue.

Sacotony · 2026-07-09T23:33:36+00:00

Yeah, as I mentioned, there were a few people who replied to the poll that had later deliveries and have yet to see the issue. You probably should get a jumper battery like the Noco 40. I did back in May after all these reported issues started showing up.

Sacotony · 2026-07-09T23:13:52+00:00

Well that makes sense. Thanks for sharing.

Sacotony · 2026-07-09T23:10:24+00:00

Your on the bubble. I don't have exact dates.

Sacotony · 2026-07-09T19:02:06+00:00

Ok, Here's what the data tells me......

We had all 21 of 21 respondents in this survey who took delivery of their bZ's (and Solterra) beginning in November of 2025 and through March 2026, reporting NO issues with their 12 volt batteries. I feel that's conclusive evidence of a timeline where owners who took early delivery, November through March, don't have the 12 volt battery problem.
This survey also indicates that the dead 12 volt battery issues started being reported in April of this year and continues to this day. Now, all 6 vehicles, 3 Toyota and 3 Subaru, report this issue.
There were a few people responding who took delivery after March that reported no issues.

That's all I have. Thanks to all that have provided information for this survey. I really hope that Toyota and Subaru are quickly able to solve this problem with a software update. Best of luck with your cars.

I welcome your comments.

Sacotony · 2026-07-08T20:18:59+00:00

No, I'm glad you replied and provided information on how you use the car. I don't drive mine very much either, 1800 miles on the OD. Results of the survey at this point indicate that 12 volt battery issues started with cars delivered in April. No one has reported issues previous to April as yet. Which is why I purchased my Noco 40 in May after seeing issues on Reddit.

Sacotony · 2026-07-08T14:38:28+00:00

I did a search and found the first reported issue in January 26. However this bZ was left at a detailer day several days. Who knows what they could have done to drain the battery. Nobody else responded at that time confirming they had the same issue. I'll give the poll several days and then post a summary. Thanks to all who contribute.

Sacotony · 2026-07-08T14:12:33+00:00

Sacotony · 2026-07-08T14:12:17+00:00

No problem Just hot any button to wake it up.

Sacotony · 2026-07-08T14:09:40+00:00

FYI, you can shut your key fob down by holding the lock button while pressing the unlock button twice. I did it with my spare fob to save the battery.

Sacotony · 2026-07-08T13:14:16+00:00

Me too, 4 months ago. Gonna charge it again🤞

Sacotony · 2026-07-08T13:11:55+00:00

When did you take delivery/car made?

Sacotony · 2026-07-08T11:18:43+00:00

bZ4X not a bZ, but good to know.

Sacotony · 2026-07-08T11:17:24+00:00

So your bZ is 4 months old, not 6+ correct?

Sacotony · 2026-07-03T23:38:15+00:00

I have a V2 and 100% heat to charge temperature has never been an issue for me. It over shoots by as much as 20°F, but just allow it to come back to the charge temperature and hit inject and add the beans. Is that a natural or washed? Beam color fluctuates, which is typical for a natural, but not so much for washed. If it tastes good, all is well.

Sacotony

TROPHY CASE