Failing battery, inverter, both?

Discussion in 'Gen 2 Prius Technical Discussion' started by respun01, Oct 1, 2019.

  1. respun01

    respun01 Junior Member

    Joined:
    Sep 29, 2019
    25
    5
    0
    Location:
    California
    Vehicle:
    2007 Prius
    Model:
    N/A
    I inherited a 2007 gen 2 Prius with 50k miles and a possibly faulty hv battery last year, had my local dealer replace the battery, engine and inverter coolant, and trans fluid, and it has been running pretty good so far. Yesterday the red triangle, exclamation with the circle, vsc, and check engine lights came on while I was on the freeway and the car started slowing down. I stopped and let the car rest for a bit and then started trying to limp the car back home. I could go about 20 miles before the ice engine would rev high and the car would start to slow down. I got as close to home as I could and had it towed the rest of the way.

    Luckily I bought a mini-vci a while back, so I checked what codes are showing.

    I'm getting codes P0A78-282, P3000-123, P3024, C1259, C1310, C1378. I was getting P3024 with the original battery, which is why I had it replaced.

    My first thought was maybe the inverter is getting hot due to the way it will run for a bit before acting up. The inverter pump seems to be working as there is flow in the reservoir, so I'm not sure there.

    I'm new to Prius troubleshooting and I'm not sure if any of these codes can also trigger the others, like if a failing inverter will cause the battery to throw codes or vice versa.

    Any insight into my fun little problem would be greatly appreciated.
     

    Attached Files:

  2. respun01

    respun01 Junior Member

    Joined:
    Sep 29, 2019
    25
    5
    0
    Location:
    California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Update: I cleared the codes and the car started up and drove just fine. After a short test drive C1378 came back, so after some searching I found a post mentioning the brake power supply near the 12v battery. I checked all the plugs near the power supply and everything looked good. I decided I’d clean up the 12v battery connections and chassis ground while I was there. Cleared the codes and test drive once more and no more C1378.

    It was a bit jerky at starts/stops previously, but smooth as silk now.

    I’ve read the Prius is sensitive to 12v but could a slightly dirty 12v battery connection cause all this trouble?

    tldr: cleaned 12v battery connections and where the ground connects to the chassis, and all is well?
     
    donbright likes this.
  3. w2co

    w2co Member

    Joined:
    Dec 11, 2009
    364
    79
    0
    Location:
    Longmont, CO.
    Vehicle:
    2006 Prius
    Model:
    N/A
    Absolutely! Also check your aux 12v battery voltage, I like to check it with a voltmeter up front in the engine compartment drivers side main 12v fuse box jump pin after its been off for a while. That jump pin is directly connected to the 12v battery and if low, can cause all kinds of ghosts. At resting (vehicle off for at least 15 mins) it should be anywhere between 12.2 to 12.6 volts depending on condition of the battery. When running it should be 14.2v, I don't know why they regulate it for so low a charging voltage, my optima battery needs more like 14.6v to reach 100%. I now use a maintainer to keep it charged up when vehicle not in use!
     
    #3 w2co, Oct 3, 2019
    Last edited: Oct 3, 2019
    donbright, bisco and respun01 like this.
  4. respun01

    respun01 Junior Member

    Joined:
    Sep 29, 2019
    25
    5
    0
    Location:
    California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Thanks for the reply! I just checked and it’s at 12.5v, it was also replaced around when I had all the other work done, so looking good there. I’ll have to keep the maintainer idea in mind, is there one you would recommend?

    I was logging with torque before I cleaned the battery connections. I’m looking at a log and I noticed that during a drive the aux 12v battery voltage was slowly falling and was at was at 12.6v by the end of the drive. I guess I’ll be doing some more logging today.
     
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    95,253
    43,192
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    have it load tested at an auto parts store. there is a date code on top, if it is older than 5 years, just replace it.

    if not, put it on a charger overnight, and keep an eye on the resting voltage.

    is it a new oem hybrid battery?

    if all else fails, you can troubleshoot the codes at techinfo.toyota.com
     
  6. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    15,172
    10,559
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Keep us posted as some more time passes.
     
  7. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    5,869
    3,121
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    I have been monitoring charging voltage for several years, and can tell you that the charging voltage can be anything from 13.2 V right up to 14.7 V.

    Your observation of the charging regime being gentle is congruent with my observations, so if the car is not getting regular and long drive cycles, it is on a maintenance charger.

    Another of my observations is that for the charging voltage to get to 14.7 V, it usually means the car thinks the battery is totally flat. Another thing is, if I see the charging voltage is 14.4 V or higher for any length of time, that is my signal to give the 12 V a full charge on my external charger.

    If your car is charging the 12 V at 14.7 V constantly, it is a pretty good sign that you need to change the battery. Constant charging at that rate will also impact the fuel consumption.
     
  8. w2co

    w2co Member

    Joined:
    Dec 11, 2009
    364
    79
    0
    Location:
    Longmont, CO.
    Vehicle:
    2006 Prius
    Model:
    N/A
    I've noticed that after a drive (10-30mins) and you're back home and ready to check it, wait until the entire cycle is over, (after it's done with all the automatic noises etc.)..if you hook up a maintainer too early, this will confuse it! Example: after shut down within about 3 minutes it will have a rather loud purging sound and also the gas tank vent solenoid goes off, all these things will draw current out of the aux. battery and will bring the voltage down to perhaps 11.9-12.0v! But after they are done it will slowly creep back up to its resting voltage. This is when to hook up the maintainer. BTW, I now use a Schumaker SP3.
    I like it because it has a readout of %charge, then when it hits 100% it goes into maintenance mode.. Just use the "jump pin" in front engine compartment drivers side 12v fuse box, First connect the - lead to a strut tower bolt for frame ground, then connect the + lead to the jump pin. That "jump pin" is directly connected to the aux 12v + post so no messing with the battery itself or fumes in the rear compartment etc..
     
  9. w2co

    w2co Member

    Joined:
    Dec 11, 2009
    364
    79
    0
    Location:
    Longmont, CO.
    Vehicle:
    2006 Prius
    Model:
    N/A
    The other reason to use a Schumaker SP3 is because the leads are totally dead when first connecting the leads! This I believe is very important because with 5 ecu's running all the time, you could zap one or more by hooking a live charger to it. Especially if it sparks! ecu's do NOT like sparks...
     
  10. respun01

    respun01 Junior Member

    Joined:
    Sep 29, 2019
    25
    5
    0
    Location:
    California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Sorry for the delay on the update.

    It’s been running good, but it threw P3024 about a month later, and again a couple days ago. I just figured out logging with techstream, so I went for an hour long drive while logging and I caught something.

    About 40 minutes into my drive B+ goes from a steady 14v to 11v. 20 minutes later as I’m pulling in my driveway the abs system is beeping because B+ had come down to 10v. Parked and came back 15 minutes later and it fired up like nothing happened.

    So, has anyone seen the converter stop charging like this?
     

    Attached Files:

  11. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    5,869
    3,121
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    So at that point, I'd expect there to be some codes thrown. Have you read the codes after the drive? Usually, you would get something like C1241 and others when that happens. How is your inverter coolant pump? If it looks to be working when you check it, maybe it is intermittently failing.
     
    respun01 likes this.
  12. respun01

    respun01 Junior Member

    Joined:
    Sep 29, 2019
    25
    5
    0
    Location:
    California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Yes, it did throw C1241, but nothing else. I haven't checked the inverter coolant pump yet, last time I checked it was in november probably. I don't think the inverter temps ever went above 115f (46c) if that helps. I'm looking at the shop manual right now trying to find test procedures for the inverter, but I don't know if I'll find what I'm looking for.

    The inverter is usually replaced as a single unit right?
     
  13. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    5,869
    3,121
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    Run through the test procedure for the C1241, which will also get you checking the BCPS (brake control power supply) in the back among other things.

    I noticed that the C1241 trips well before there are any inverter faults.

    You are looking for the reason the DC/DC is dropping the 12 V power.

    My hypothesis is that the inverter cooling pump is not working well enough to keep the inverter cooled enough, but not so far out of spec that it trips inverter overheating DTCs.
     
    #13 dolj, Jan 22, 2020
    Last edited: Jan 22, 2020
    respun01 likes this.
  14. respun01

    respun01 Junior Member

    Joined:
    Sep 29, 2019
    25
    5
    0
    Location:
    California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Haha, I suppose that does make sense, I tend overthink it sometimes. I guess I've got some work to do in the morning.

    Thank you dolj!
     
  15. respun01

    respun01 Junior Member

    Joined:
    Sep 29, 2019
    25
    5
    0
    Location:
    California
    Vehicle:
    2007 Prius
    Model:
    N/A
    I think your hypothesis is correct, it looks to me like the pump is barely running, there's barely a ripple on the surface of the coolant. I recorded a bit, so I could get a second opinion. That's in ready mode while the ice is not running.

     
  16. Glen2007

    Glen2007 Junior Member

    Joined:
    Mar 16, 2017
    31
    8
    6
    Location:
    Chicago
    Vehicle:
    2007 Prius
    Model:
    ----USA----
    P3000-123
    Abnormal signal response from the battery ECU, often associated with a high-voltage battery system malfunction.

    Possible causes include: HV battery system, Battery ECU

    you had the dealer replace the hv battery correct?
    how old is the 12 volt ? what brand?
    when I see a glob of codes from my car I know my hv battery is failing

    P3024 Possible Causes Faulty HV battery assembly Faulty Battery ECU




     
    #16 Glen2007, Jan 22, 2020
    Last edited: Jan 22, 2020
  17. respun01

    respun01 Junior Member

    Joined:
    Sep 29, 2019
    25
    5
    0
    Location:
    California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Yeah, I had the dealer replace the HV battery. I'm trying to make absolutely sure that the hv battery is the problem before I go to the dealer for possible warranty replacement.

    The hv battery was replaced roughly 1 year ago, and the 12v (optima yellow top) was replaced around the same time. The 12v still seems to be healthy, it sits around 12.5v at rest, and I've been keeping it on a tender every couple weeks to make sure it's topped up.

    Earlier today I discovered the inverter pump isn't working well (I think anyways). I posted a video a couple posts up of that.

    I've been loosely monitoring the hv battery with torque over the past few months and all the blocks have been staying within 0.1-0.2v, and the internal resistances are all low, around 0.025 ohms. And the only code it has reproduced was P3024, but I haven't seen block 14 actually go low, even in the freeze frame data from the first time it happened in the first post.
     
    #17 respun01, Jan 22, 2020
    Last edited: Jan 22, 2020
  18. Glen2007

    Glen2007 Junior Member

    Joined:
    Mar 16, 2017
    31
    8
    6
    Location:
    Chicago
    Vehicle:
    2007 Prius
    Model:
    ----USA----
    Have the tools ready to disconnect and reconnect the 12 v negative battery cable in case you get the triangle of death. Practice this before you get the triangle of death then you will be prepared. You may find order and peace if you are prepared. If the triangle appears before you remember your training remain calm a 12 v reset may limp you home.
     
  19. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    5,869
    3,121
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    Yes, I agree, it looks like it is barely doing anything.


    I'm not sure making such an assumption is even a good idea let alone that, in general, making assumptions is a bad way to diagnose a problem.
    Umm, actually P3000-123 doesn't say possible causes are HV battery system, Battery ECU, it says those are trouble areas:

    P3000-123
    Detection Item:
    HV Battery Malfunction

    DTC Detection Condition: Abnormal signal input from battery ECU (HV battery system malfunction)

    Trouble Area:

    • HV battery system
    • Battery ECU
    While it is tempting to go all Chicken Little when you see the words HV Battery, it is a good idea to look at the big picture.

    The key with P3000-123 is to focus on the detection condition, where you will see that it simply is the HV control ECU is telling the driver that it heard from the battery ECU that there was a problem. This could be because the inverter is not performing, for example.

    Second point, the codes were cleared and did not return. It may be that they were residual from a previous event and not current.


    Rather than get side-tracked, my inclination would be to change the inverter coolant pump (or have it changed), as it seems to be hardly doing anything at all.

    After doing this I would redo the same hour-long drive (if possible) while logging and see what transpires.
     
    #19 dolj, Jan 23, 2020
    Last edited: Jan 23, 2020
    respun01 likes this.
  20. respun01

    respun01 Junior Member

    Joined:
    Sep 29, 2019
    25
    5
    0
    Location:
    California
    Vehicle:
    2007 Prius
    Model:
    N/A
    My thoughts exactly! I already ordered a new pump, but it won’t get here until early next week. I’ll post an update with results.
     
Loading...