Same. This issue alone is causing some pretty big pangs of regret in regards to this truck…..the deaf ears of the dealership is most maddening.
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12v battery (hybrid) runs low after sitting for a week
- Thread starter MustardTiger
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Half considering a hood mounted solar battery tender for piece of mind. I don't do long through hikes anymore but its crazy to think that I wouldn't have been able to leave my truck at one end of the John Muir Trail while i hiked it.
Thanks, something in the charging system seems wonky If it’s sometimes applying 13.8v and other times not. Also seems like a lot of drawdown overnight - logout of the Toyota app to rule that out as a source.It's the original battery. I've circled the voltage of me driving.
Given that some like yourself have an issue, and other people don’t, it suggests a faulty component or something.
I’d push hard on the dealer to find what’s wrong. Hopefully you can get it sorted. If it were me and they gave a BS excuse, I’d start documenting what would be needed for a lemon law case.
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I've got a laundry list for the dealer when I have the time to burn. The OBD2 port falls out because the dealer replaced it with an aftermarket tracker, back passenger tire leaks super slowly, no punctures. And an annoying rattle with the trim in front of the front doors as identified in this thread. Rest assured I'll keep them busy one way or another.
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- #110
Has anyone notice a change in the behavior of their voltage gauge? I’m wondering if Toyota has issued an OTA update or something because mine is always at this level now…
before it was mostly always below the battery graphic
before it was mostly always below the battery graphic
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Sometimes mine is in the middle of that little battery, particularly when it first starts. But then it settles to left of the battery graphic and pretty much stays there.
I drove my truck a couple of hours this morning and now it is at 12.1 volts as usual. I have a service appointment in two weeks and I will see what the dealer has to say. My guess is they will say that this is normal for the hybrids, which could be true, but don't leave it parked for long or expect the battery to last a long time.
I drove my truck a couple of hours this morning and now it is at 12.1 volts as usual. I have a service appointment in two weeks and I will see what the dealer has to say. My guess is they will say that this is normal for the hybrids, which could be true, but don't leave it parked for long or expect the battery to last a long time.
I have been looking for the voltage display and have not been able to find it.
So, now you know I am no good at this.
I do have some stuff to add.
From reading other folk discus the hybrid charging system with no alternator.
These is what I understand about it but double check my data to be safe.
1-Toyota wants the hybrid bank around 50% charge.
2-The system charges when braking and, I think also when downsizing and foot off the accelerator
My 24 PF has been left in the garage for 5 weeks and another time 4 weeks and started ok.
You should gave yours checked.
So, now you know I am no good at this.
I do have some stuff to add.
From reading other folk discus the hybrid charging system with no alternator.
These is what I understand about it but double check my data to be safe.
1-Toyota wants the hybrid bank around 50% charge.
2-The system charges when braking and, I think also when downsizing and foot off the accelerator
My 24 PF has been left in the garage for 5 weeks and another time 4 weeks and started ok.
You should gave yours checked.
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My 2024 has 1,200 miles. Sat for 2 weeks and 12V battery drained. This happened 2X. First time the dealer charged it. Second time they replaced the 12V battery, bad cell.
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- #114
Similar situation here. My late production 2024 had the 12v battery replaced by the dealer before I even bought it…I assume it was dead when it arrived on the transport truck. Currently at 1200 miles as well, haven’t had any issues. But I do put a tender on it when the truck sits for extended periods of time.
2024 with same issue. First time after leaving in the garage for a week on vacation. Now I can't even use the bed inverter to print one sheet of paper (about 5 minutes) without the truck running or the battery will die. Dealer said they "checked" it and the battery is fine. Only thing they said next is I can leave the truck at the dealer "for a day or two" and the master tech can run other tests to see if it is another problem. My dealer still has not gotten in the brake line. Once they do it will go in for brake line, software update for blind spot and then let them check the battery issue.
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Define “extended”. If less than four to six weeks push back hard.
A properly charged 12V lead acid battery will hold charge for well past that unless there’s excessive discharge when off.
And if the 12V battery isn’t kept at full charge that itself is a significant problem IMHO since every other vehicle achieves that as a basic rule of existence. If/when I buy a 4th gen I’ll be monitoring that and will Lemon Law it back to Toyota if it can’t keep the 12V battery charged b
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- #117
I’ve had it sit for 3 weeks without a tender and it was fine, albeit the battery was at 12.1v at the end. I’ve never had the truck not start. Now if I left it outside in -30 temps for a month…I’d probably be concerned about it going dead. But in that case I would assume the traction battery would still start the truck
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I agree, and I think that is the problem. At least in my truck the hybrid does not keep its 12v fully charged. Right now, even with regular driving it is only 12.1 volts, and that gives you a very small reserve. In two weeks mine goes to the dealer for service and I will let y'all know what they have to say.
The traction battery probably would start the truck, but only if the 12v has enough power to turn the truck on. My wife's Lexus battery electric sometimes doesn't and that is why we both carry jump packs.
I can confirm, left my Pro on a battery maintainer for the last 30 days while we were away. Attached it at the jump points in the engine bay. Seems to have worked fine, truck started right away and everything seems fine. So at least there's that.
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