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P0A80 Code- but is it really the hybrid battery

Discussion in 'Gen 3 Prius Technical Discussion' started by Mellyman666, Mar 9, 2024.

  1. Mellyman666

    Mellyman666 Member

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    Hi!

    This forum has saved my life in the past so hoping it can help again!!

    For context: I have a 2010 toyota gen 3 prius. It currently has about 130,000KM on it (about 81,000 miles).
    Around 6 months ago, I had the trecherous head gasket warning. Took a while, but thanks to your help, I successfully changed the head gasket myself (I had it checked by a mechanic before restarting and he set the timing for me).
    As background info, I bought the car used in 2022, and honestly doubt the previous owner did much of the proper maintenance work on it, so I think that's why a lot has been happening in a short period of time.

    1. About 2 weeks after the head gasket replacement: My car died- suddenly lost power, had the check battery warning light on but could not accelerate at all. I had it towed home just to find out the gas line had somehow unclipped. Clipped it back into place and everything was normal again.

    2. 1 month after the finish of the head gasket replacement, I got a P0607 code, and just at that point had noticed the red airbag light (yes I know, dumb as hell, but in my previous car, that red airbag light meant the airbag was on and working, and for some reason I assumed it meant the same thing here). In my defense, I was going through a lot of person shit at the time and did not do extensive research and did not take it to the dealer... I know, my mistake. After some research on the internet, I toggled with a few sensors under the seats, and reset the code. Never had the P0607 code come back.

    3. I eventually got to the dealer and they plugged up the machine and got the B1660 passenger seat code for the airbags. They didn't have time to do further research and the dealer told me the mechanic I knew from Toyota and who they give all their "electrical/sensor" problems to, was on vacation. Had me sign a waiver (option was either sign a waiver or leave car there, but I needed a car) and told me to come back in 1-2 weeks. I had my app scheduled for next week, where they would do more exploration for the code, but it only dawned on me after leaving that maybe I should have told them about the P0607 code, as maybe it was related (I have no idea honestly).

    4. Just yesterday (so at this point probably 2-3 months after the P0607 code), with no apparent triggering reasons, the check hybrid light came on. Plugged up my reader and got the P0A80 PERMANENT code. Besides the code, the car drives perfectly- I stopped driving it, but on the drive home from when I got the code, I saw no issues except that the battery on the display was no longer showing 80% full and the display that shows like the components with the flow of energy in the car was not shwoing anything either.

    Work/pieces changed on car already:

    -new head gasket as well as all the gaskets to be changed with a head gasket job
    -new engine air filter
    -new water pump
    -new 12v battery installed about 3 months ago
    -oil changed about 2,000-3,000 km ago

    My questions:
    1. Could the 2 codes be related? I had read that the P0607 code could be related to the ECM and am wondering if this has anything to do with the hybrid battery?

    2. My hybrid battery "seemed" in good condition. Don't know if this affects anything, but my charge for the hybrid battery gets to about 80% full all the time, so I mean if it was really the whole hybrid battery that was shot, wouldn't I not even be able to recharge it?

    3. Any pointers or general directions in which to go. I will go to my dealer app this week but am admittedly kind of panicking as I don't really want to have to change the whole hybrid battery. I read sometimes just some cells need changing, but knowing my dealer, I'm quite sure they'll suggest changing everything.

    4. I also read online sometimes the code doesn't mean the hybrid battery is dead but can be other components related to the battery (I read about a pump that cools down the battery or something like that?).

    5. I keep seeing different answers about this online, but is there any way I can check the state of my hybrid battery myself?

    6. Any things I should check or look into before bringing to the dealer this week?

    I will search the forum for similar issues, but I know sometimes it takes a while to get a response so thought I might as well post in the meantime.


    edit::: performed a test with a high class OBD and did battery testing- Hybrid battery has all green bars (see photo below).-- so why am i receiving the code if the battery pack is great? suggestions on things to check out or clean etc

    ANY help would be greatly appreciated. I am at wit's end with almost everything going wrong right now in my life that I'm really just hoping I can avoid any catastrophe or having to drop 5k on this car.
     
    #1 Mellyman666, Mar 9, 2024
    Last edited: Mar 9, 2024
  2. Tombukt2

    Tombukt2 Senior Member

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    It's a generation 3 and you're all in with a head gasket done and everything running very well It seems like you would want to get with somebody or a group maybe up in Montreal or Quebec somebody in a local group of Prius owners might have the tech software from Toyota? If you can get a hold of that you can actually see a whole lot more than you're seeing now. Do you have the doctor Prius app? If so what does it show for your battery health there's a whole screen that deals with that I have the same code in a 2010 right now I changed out the battery to a 2015 battery that's in very good health and the car runs great but even the Toyota software won't rid me of the permanent same code as you posted here The hybrid battery one so we've been driving with that permanent code for the last 4 years and apparently we've never driven the drive appropriately to make that code clear is what my understanding is of all the business what that drive actually entails I'm not positive but this car is used for delivery service so it's in the wind all day and most of the evening so I'm not sure what kind of driving would need to be done to make this permanent code disappear I've read about the drive but apparently we can't make it happen or there's something else in this.. me personally I would want to see what my battery looks like all blocks all modules the whole assembly Yes it could be your battery ECM the HV battery ECM it is possible usually those get cleaned because of funk building up on the board bars and what have you I think they're quite expensive also so you wouldn't want to buy one generally you'd want to buy one from a junk car from one of those battery rebuilding places they'll have stacks of them they're not worth anything when you've got a few hundred in your shop.
     
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  3. ChapmanF

    ChapmanF Senior Member

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    No, P0607 is about the ECM's ability to control the heating current to an oxygen sensor. Could implicate the sensor, wiring, the ECM, or a leaky exhaust system. If that code comes back, there are six pages of troubleshooting ideas in the repair manual that can be followed.

    Toyota Service Information and Where To Find It | PriusChat

    Was it only showing in the 'permanent' column, or also in the 'current' column?

    If only in the 'permanent' column, it could be the memory of a code that was only current once in the past. But just having a memorized permanent code doesn't turn warning lights on, so there should have been at least one code showing as current.

    No, the ECM specializes in controlling the gasoline engine, and the codes aren't related.

    The 'state' of the battery (in the sense of its distance from cradle to grave) is a complicated mix of things. There are some tests you can do (you'll see answers about this online) that will be like snapshots of a few of the things the battery ECU monitors continuously, but because the ECU is able to monitor them all and relate them in real time, its opinion is likely more dependable than yours. By showing P0A80, it has given you its opinion that the battery is now far enough from cradle to grave to be worth doing something about.

    The "with no apparent triggering reasons" simply reflects that the battery has been on a steady slow trajectory its whole life, the ECU has been watching that, and there will always come a day when the trajectory crosses the "yup, show P0A80" line. The day before, it was just on the other side of the line, is all.

    The dealer will definitely just offer replacement; they aren't in the whack-a-mole module replacement business. As a DIYer, you can pursue the module-level replacements if you choose. Sometimes you'll get a lot more trouble-free driving before whacking the next one, and sometimes not.

    P0A80 is a pretty specific code. A car can have other hybrid-system issues, like the pump that cools the inverter (not the battery), but those situations have their own trouble codes.
     
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  4. Mellyman666

    Mellyman666 Member

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    I borrowed an advanced OBD reader and got this on the battery health page. Also my battery recharges- I erased code and drove maybe 10km today and battery recharged with braking.
    I added all the diff codes I got with this « better » machine. I am out at the moment but will read all responses tonight but just found it odd this OBD shows as if all battery cells are in the green…
     

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  5. Mellyman666

    Mellyman666 Member

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    I read all your answers; I’m just wondering with the « health check » of my battery, what should I do as the next step? I’ve seen online suggestions of cleaning out the fan, some of cleaning the metal plates attaching to the battery, some showing to just test each battery and change out bad ones but I don’t know on that OBD shows as if all are ok? I’m much better on the mechanic side than the electric side lol but I just don’t want to change out the whole battery like the dealer will tell me to do, if the battery can be repaired or if it’s something else causing the battery to appear as « in need of service »
     
  6. Brian1954

    Brian1954 Senior Member

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    Trouble code P0A80 for the HV battery is listed as a permanent code, so you do not need to be worried about it. If the HV battery is good, the permanent code will clear at some point. If the P0A80 is listed as current, then you need to worry about it.

    Do some research about the Dr.Prius app, which is good for evaluating the HV battery.
     
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  7. Tombukt2

    Tombukt2 Senior Member

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    At some point take a look at your battery cover under your battery cover Do you see the bus bars they're supposed to be bright copper then now turning black maybe a bluish color the nuts holding the bus bars on in their yellow holders and all that You see them starting to frost? If so these things will hold up electricity lot of times just cleaning the bus bars in the nuts dressing the fittings whatever it is you do can make a huge difference just the Prius being a car out in the open maybe parked outside so on and so forth It's kind of like a boat you know just has a roof as you see by post here rodents get in and out of these things trunks can leak all of it can be like a terrarium in some of these vehicles that will take its toll on bus bars and nuts and things like that on a battery I just cleaned one up last week maybe a huge difference I mean it's like night and day practically It may not last long The battery is 8 years old 10 is nominal or max life for the most part so there's always that but I guess you can't complain about every lasting 8 to 10 years for the most part that's pretty good sure isn't Dad's Duracell.
     
  8. ChapmanF

    ChapmanF Senior Member

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    None of the photos in #4 show any current code about the battery at all, so there's nothing there showing any current reason to be worried about it. "P0A80 permanent" means the car still remembers some time in the past when it showed a P0A80, but it doesn't mean that code applies now.

    Question, though: have you got the triangle-exclamation warning light, or the "CHECK HYBRID SYSTEM" message showing? There has to be some current hybrid system trouble code, if those are on.
     
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  9. Mellyman666

    Mellyman666 Member

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    With my shitty OBD reader, it was telling me 1/3 as if there were more codes, but wouldn’t allow me to see them. I’m worried one of those other 2 were a current P0A80. With the more advanced OBD it says just permanent. Any way to know if there’s actually a current code or not? also any reason the P0A80 code permanent would pop out randomly without me having done work on that area of car?

    If you see my reply earlier on, I added a pic of the « hybrid battery health » and it seems okay, leading me to believe it’s an old code I just don’t get why it would pop out now. I also cleared it, drove 15km and never came back. But the problem is as soon as the code does go on, the whole « Hybrid » part of the car doesn’t work (hybrid battery on screen shows as empty, shows that it isn’t charging with each break, and I’m not able to put the EV mode on.
     

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  10. ChapmanF

    ChapmanF Senior Member

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    Something's not adding up. You're talking about a code you can clear, and then about when it "does go on" (how can you tell when it goes on? Do any warning lights or messages come on, or do you only notice the behavior changes you've mentioned)?

    That sounds a lot like a 'current' code. A permanent code is different: it doesn't put any warning lights on, it doesn't change the behavior of the car; it's just the car remembering that code was detected once. You can't really clear a permanent code; it goes away in its own sweet time, only after being satisfied the problem's all gone. You can follow a confirmation driving pattern if you want to satisfy it sooner.

    Could it be that this Innova is showing a code as 'permanent' when it really means 'current'? Seems weird.
     
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  11. Mellyman666

    Mellyman666 Member

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    I got the « check hybrid system » code yesterday. It was accompanied by a check engine light, the yellow triangle warning and something else I don’t remember. Checked it with a crappy OBD reader and it said permanent but there were other codes too (had a little sign like 1/3) but the other codes would not show up. with that crappy OBD reader, I erased it. When I erased it the big « check hybrid system » warning went away, and so did all the lights that popped up with it. When it did have this light on, the battery symbol on my dash was empty (when it’s normally 80% full) and I wasn’t able to activate EV mode.


    today I took the car for 5-15km, the « check hybrid system » warning was gone since I clicked erase (which also leads me to believe there was a current and a permanent code). I went to get my friend’s high tech OBD reader, and plugged it, and it showed only the permanent code BUT NO LIGHTS WERE LIT UP (since I had clicked erase). When there is no active light on the dash, the hybrid system works fine, battery appears as 80% full and the EV system is working.

    The innova OBD that I had yesterday (the really basic crappy one) I feel showed both a permanent and current code (but didn’t allow me to switch between screens to view the codes!), and when I clicked erase, it erased the current one,but the permanent one didn’t erase, hence why with the high class OBD, only the permanent one came on.

    my question is, since the hood OBD shows the hybrid battery is In good health, and there are no signs of battery dying, is there something else I should check before going to dealer and having them change the whole battery, since the battery « seems » ok?

    i also posted a pic of the other codes I got when I did a full scan, because I don’t know what they are and putting them in case they mean something.
     
  12. Mellyman666

    Mellyman666 Member

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    Yes I got the yellow triangle only yesterday when the check hybrid words first popped up. Once I clicked erase on the first OBD reader, the triangle disappeared
     
  13. Mellyman666

    Mellyman666 Member

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    I will do all these verifications tomorrow. Seeing as I’ve never worked on a hybrid battery, might seem like a dumb question but is doing all these cleanings and verifications safe? Or is there some sort of electricity danger?
    Also since the « potential current code » is erased and hasn’t come back, should I drive the car and wait for it to come back or stop driving altogether
     
  14. Tombukt2

    Tombukt2 Senior Member

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    I use an even cheaper in over brand scanner I think it's a 3210 looks like this but older and it definitely discerns between permanent and when it's not permanent it's just a code there's no word permanent below it or above it and there may or may not be freeze frame day to depending upon the type of code on the Toyota Prius It will not read everything but it does a dang good job I rarely have to get TS out to be honest about it unless it's something really weird and other than the standard things we know like inverter cooling pumps and all this sort of thing so the enova was given to me actually buy a mechanic that died his wife gave me a lot of his things and this was in it and he was a GM guy so I just figured whatever but then I started using the little thing and it actually did quite well and I was quite surprised pleasantly I guess
     
  15. Tombukt2

    Tombukt2 Senior Member

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    Yeah you need to kind of have an idea what's going on cleaning and doing stuff back there so probably better not watch some videos get a better idea of what's happening and then maybe one day take something like the doctor Prius app and monitor your battery for a little while and see what you see like I say we have a 2010 with a permanent same code It's never cleared The car is very weird but that's another whole deal in itself so I wouldn't worry about it if your car is driving well and things look relatively decent and Dr Prius the battery monitor part of it then you're probably generally speaking okay till you tax the battery climbing and descending hills or whatever a lot of them or something like that You may not notice anything maybe in the summer time with the air conditioning on things will change we'll see.
     
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  16. Mellyman666

    Mellyman666 Member

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    You say the code in yours doesn’t clear, but it’s not active right? Like the big « check hybrid system » sign and he triangle isn’t on? And if it is, does your hybrid battery still charge and/or work? Cause mine seemed to like just disconnect as soon as the big warning sign came on.
    And yes I think my model is similar, it’s a yellow 3210 I think
     
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  17. Brian1954

    Brian1954 Senior Member

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    I would not do any cleaning or disassembly of the HV battery until you know what the trouble code is that is triggering the lights on the dash. The HV battery is high voltage and can be dangerous if you do not know what you are doing.
    I would drive the car and find out what the code is so that you can start the diagnostic poscess to fix the problem. Make sure you have a good scan tool with you at all times and do not clear the trouble codes until you have retrieved all of them.
     
  18. Tombukt2

    Tombukt2 Senior Member

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    No in my 2010 solar roof car I replaced the battery about 5 days after I got the car with a junkyard 2015 battery when I did that the code moved from being active and I never really checked it I didn't even know it was permanent We were just driving the car using it blah blah blah then a few months later I actually bought the real Toyota software on a toughbook computer with the VCI cable and everything so of course I went over to the car and connected it up was running great with no issue we just figured we'd try out the new software plugged it up ran everything did a health check and this code popped up as being in there and permanent there are some driving procedures you can go through apparently to help clear this up or what have you We didn't pay that any mind We just closed up the computer turned everything off and she kept using the car for Uber eats DoorDash and Amazon flex put $170,000 mi on that battery and it still working fine but the code is still there no triangle no anything for the whole $160 some odd thousand miles so far and now it's rattling in the head gasket is the issue and we're probably not going to fix.
     
  19. ChapmanF

    ChapmanF Senior Member

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    Probably was a current P0A80 then, with only the permanent record showing up later, after 'erase' cleared the current one and turned the warning light off.

    Yay for permanent codes—otherwise there'd be no record of what code had been there and been cleared.

    The parameters the car looks at to set a P0A80 are pretty specific to the condition of battery modules themselves, and not so much to other issues like the internal wiring or tarnish on the bus bars. It might not 'hurt' to look at those things (provided you know how to do it without getting hurt) but expecting to find a quick fix there will probably lead to disappointment. Problems like broken voltage sense wires have their own different trouble codes.

    You may find that the bus bars can look quite tarnished where you can see, but will be shiny clean under the nut flanges where it matters. As long as the nuts were properly torqued and haven't been disturbed before, those connections have been gas-tight from the time they were torqued to the time you loosen them to see underneath. ;)
     
  20. Mellyman666

    Mellyman666 Member

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    So if the hybrid battery is in good condition (atleast according to the EV battery test on OBD) do I just continue driving until it happens again? But if it happens again, and it does the same P0a80 I’m asking myself how will I be more advanced as I still will have a code telling me to replace the battery, but the battery test shows the battery is fine.
    I was thinking of trying to go to dealer and explain the situation and ask them what else could be a cause but worried that even with the test showing all 14 cells are good, they’ll want to change the battery cause of the p0a80 code :(