2012 with Service Hybrid System warning

The latest on this.
Dealer said they can’t initiate a ticket or whatever with Toyota regarding the lost communication issues until the unrelated codes are resolved.
That involved the intake being replaced, to resolve the P0304, according to them, so I let them.
We had it back for two days when the random lights and codes returned, minus the P0304.
It went back this past Sunday.
They called today (the service manager) to say they can’t find anything out of the ordinary other than the battery being almost completely discharged. The 12V battery.
They can’t say why it was discharged, as they charged it and it held a charge, or has so far.
They want to keep it tonight and run a few tests in the morning. Their only suggestion was to either replace the new battery with another thinking it has an internal problem, or replace with a genuine Toyota battery.

I am a bit concerned that they have no idea why the 12V battery is randomly losing its charge.
I don’t know how it’s charged, or what controls that aspect of it, but I’d think whatever that is may be the culprit, not the battery itself, but again, I have no idea.
Talk about frustrating.

 

I would, but there are none that really specialize in hybrids. I don’t feel like I’d be any better off with any of them than myself.

 

Yes, it never sits. About 100 miles a day in and out of town. Well, dealer said it needed charged, but was new, Napa Gold AGM battery, so it should be ok, tested good before I installed it.
How would I go about confirming it’s the inverter?
And then I have to figure out how to get them to test it, or replace it.

 

Wife picked it up today.
Service manager and all mechanics gone.
They claim the issue is the incorrect battery installed. They say if it happens again (it will), that we need to put a Toyota battery in it.
Good lord, there are less and less good mechanics anymore. Most these days seem to throw parts at it until it’s fixed rather than follow procedures to diagnose and troubleshoot issues.
So because I’m fed up with all of this, I’ll get the dang Toyota battery and when it happens again, I guess they’ll pay me back for it.

To be continued…

 

They claim to have two certified master hybrid techs.
I have no problem replacing the battery, if that’s the issue, but I just did a month ago, with Napas AGM, tested before install, and better than the OEM battery. It’s gone bad in a month? Not impossible, but it doesn’t seem very likely without something else going on. Had I not tested before install I might be a bit more inclined to think it might be an issue. But then we have the charge issue.
If there weren’t another issue, why is it not maintaining a charge while the car is being driven?
That’s something no one at the dealership seems to be interested in, or able to answer so far. Or why it happens, then the car will be fine for a week, then not. If the battery were an issue, this should occur very regularly, as a battery is pretty darn simple and isn’t going to fail, fix itself, then fail again, then repeat.

Something my wife mentioned, since it’s her car, the warmings seem to occur more frequently on longer drives, say 45 minutes or more.
I don’t know if that means anything or not, but it almost sounds like something is getting hot and shutting down or otherwise having some kind of issue after long periods of working.

 

It is the Legend AGM, not gold AGM as stated somewhere above. They don’t make a gold AGM, not sure why I said it was a gold.
Better as in more tested amps than the Toyota battery, and much easier to get. 7 year warranty is great, but it’s prorated.
If a battery meets rated standards for amp hours, cranking amps, etc, there should be zero issues, regardless of claimed warranty period.
I’ve seen lots of folks here and other places using non-OEM batteries in Priuses with nary an issue, so Does that mean ours is special?
As I’ve said, if ours REQUIRES a Toyota branded battery, fine, but that doesn’t address why it’s discharging while the vehicle is being driven.

 

They tested that, as have I.
Unless I can run both of those tests somehow logging data while the car is being driven over the course of a few days, it’s not all that helpful, and I don’t have that capability.
Parasitic drain while sitting is irrelevant here, as it’s happening while the car is in use.