2007 Prius with many warning lights

Bad hybrid battery.

Your mechanic is correct it was killed from lack of use. There dropping like flys these days because no one drives much now.

Start reading all the threads on here about hybrid battery repair for your options.

 

Maybe.

But just sitting is MUCH harder on the 12 V battery than on the big one.

Before you spend a lot of money on ANYTHING, be sure that your 12 V battery is charged, healthy and the connections are good.

And if it is more than 5 years old, be prepared to replace it.

 

Nope


He’s got the red car icon in the upper left corner of the mfd. that’s not a bad 12 volt battery thats hybrid battery failure.

 

Well, the red car icon means a problem has been reported by the Hybrid Vehicle ECU. Battery failure is one of the problems the HV ECU can report, but there are a hundred or so others, some of which don't require deep pockets to fix. It would be worthwhile to ask it what it's notifying you about, before jumping to one of the more expensive possibilities.

 

AND.....if the 12 V power supply is weak, you can't depend on ANY of the notifications being accurate.

 

On the other hand, those of us who do expect the notifications to be accurate nearly always find our expectations fulfilled (including accurate notifications that the power supply got weak, if that happened). While the supply can get weak enough to impair operation of the computers, if you have to argue about meter readings to decide if it's that weak, it isn't. The repair manual does instruct to give it a charge or replace it if it's below 11 volts before proceeding, and that's reasonable.

There are those who will insist that even minuscule deviations from some ideal charge state render it pointless to even find out what the car thinks it's saying, and who will no doubt continue to so insist. It takes all sorts to make a world. Some will collect all of the possibly relevant diagnostic information earlier than others.

 

REALLY ??
Then why do YOU never mention that ?????

If that is reasonable, then the posts that you make on here......that never even mentions anything about the 12 V system.....is grossly UNREASONABLE.

Why do you have so much of a problem SEEING that ??

Blindly expecting the codes to be accurate is just being foolish.

And as long as you fail to mention that, I will continue to "fill in the blank" for you.
You continuing to complain about that is just wasting everybody's time.

 

Hmm ... yeah, that's a good question ... why do I never mention that?

Why didn't I mention that here, I wonder?

Or here?

And why on earth did I pass up the chance to mention it here with a screenshot from the manual? It would have been so hip and multimedia-like.

Truly negligent of me ... I must say you've got me there.

And it's not just those Gen 3 manuals ... I mean how would the dear folks who wrote the Gen 2 manuals feel if they knew how I never mentioned their daring, exhilarating ten volt threshold?

Like the way I never mentioned it here ...

or here ...

I mean, it's just crazy the way I never mention that. You'd probably better keep filling in those blanks. Otherwise, who knows when I might never mention it again?

Who's complaining? I just pop around every now and then to make sure people reading your posts can also get accurate information.

 

OK, so "never" was a stretch on my part. It certainly SEEMS like never.

Those examples that you gave are easily offset by the posts that you have made that does NOT make any mention of checking the 12 V battery and instead running off and chasing the trouble codes that are present.

And then there are your rants of protest when someone ELSE suggests first checking the 12 V where you claim that one should treat the computer generated trouble codes as infallible. BUNK.

And further, when you do mention the 12 V system, it is down at the bottom of your post....usually.....where many people might not even read that far.

SO.....if you will continue to tell the whole story, in the right order, I will get off your case.
If not, then you aren't done with me yet.

 

I have a question for you Sam, in your posts why do you never qualify what "weak" or "bad" is, in the context of the 12 V system. Because the repair manual does, and in some mentions, the computers will still function and give accurate freeze frame data right down to 8.5 V and lower.

While that level might not enough to run the car reliably, it does say to me that I can trust what the computers are telling me even right down to that level.

Generalist advise is useful to a point, but those that own the Gen 2 and refer to the repair manual might just actually know a bit more than an EET who doesn't even own a Gen 2 but nevertheless flits around all the Gen 2 forums looking for the word battery to pop up and then start long-winded arguments (that, most times, only serves as a distraction based on his general knowledge) that may or may not apply to the specific Gen 2 problem in the discussion.

You might just be gracious enough to concede you are not always right.

 

Sound general principles are never "wrong".

The power available to the computer boards is dependent on a lot of things in addition to the output voltage at the battery.
A slightly loose or corroded connection might take that 8.5 battery voltage down to 6 or less at the board.
So can another component nearby that is malfunctioning slightly and drawing more than it's share of the available power.
Those factors might not come into play if the battery voltage is 12.5 or above.

And there have been a few posts where I advised that the readings were a bit too low to be reliable.
That becomes a possibility around 12.3 volts and becomes more likely for every tenth lower than that........down to about 12.0 where an AGM battery is about half discharged. At that point, I don't think it is reasonable to trust it......even if that is not the root cause of the problem. At the very least, it should be fully charged before any further troubleshooting is done.

I never said that I am "always" right. Far from it.
But on some things, the facts speak for themselves and the person delivering the message is not important.

How about we concentrate on giving out good information and not taking pot shots at each other for senseless disagreements ??

 

All of that is true, but if a technician was serious about fixing such an issue (or collection of issues), digging into those dependencies and where they might be broken would be a better approach than just charging up the battery to mask the problem – if, in fact, that is what it was. I have seen no evidence to support your notion that a 12 V bus voltage at or below 12.3 V is a problem. Do you have such evidence relevant to the Gen 2 Prius? I prefer to support the Toyota engineers/technicians when they advise a tipping point (which in my opinion is always conservative) of 10.5 V, 9.5 V, 8.5 V, or the relevant threshold that is detailed for a code in the inspection procedure (or, in fact, any part) of the repair manual. I will continue to push back against misinformation that is just an uninformed opinion.

While on the face of it, all that sounds plausible. Maybe in a generalist 12 V battery specific sense, but specifically, again what evidence do you have that says 12.3 V is the tipping point for any sort of problem in a Gen 2 Prius?

So, would it be more accurate to say, " At that point, In my opinion, I don't think it is reasonable to trust it", rather than portray the statement as fact?

True, but sound principles can be misused or used out of context. I see most often when people have an incomplete picture of a system and then struggle to make sense of what they see. They then try and create a narrative that fits their level of knowledge.

The tone of your posts, never making room for another point of view, always having to have the last word, says that.

True.

True.

Let's do that but equally, stop spreading misinformation in the guise of fact.

I only push back against the misinformation. Senseless is your word, not mine, but I'd be happy for the senseless hijacking and derailing of every battery (or multi-DTC) thread in the Gen 2 forums. Feel free to knock yourself out in the Prius c forums.

And by the way, I do not disagree with everything you say, and I appreciate the effort of late you have made to post respectfully and factually. Even I was surprised that I could agree with those posts. Some of the non-battery posts have been interesting and informative and I'd like to more of that expertise brought to these forums. Keep up the good work.


Shall we get back on topic and discuss the OP's topic "2007 Prius with many warning lights"?

 

Thank you for the good words.

I wish I could return the good words but.......after reading most of your "true BUT......" post, I just don't quite see the point of most of that.

If you want PROOF, look it up yourself.

Otherwise, don't worry about it........ESPECIALLY if it doesn't affect you.

P.S. If you will notice......or go back and check.......I believe that I did NOT say "If your battery voltage is XX.X or less, then it is definitely bad". What I have been saying all along is " You need to test the battery and it's connections. If it is below XX.X it is suspect." "Suspect" does not mean bad. And it does not mean to blindly change it out based strictly on a guess.......unless maybe it is over 7 years old or so.
And yes sometimes I have said it might be a good idea to change one that is 5 years old.
Sometimes that IS a good idea.