1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Please help: HV Battery or ECU?

Discussion in 'Gen 3 Prius Technical Discussion' started by Rodriguezintexas, Jun 15, 2017.

  1. Rodriguezintexas

    Rodriguezintexas New Member

    Joined:
    Jun 15, 2017
    8
    0
    0
    Location:
    Wylie, TX
    Vehicle:
    2010 Prius
    Model:
    Base
    Hello. Thank you in advance for your time and assistance. Please assume I know nothing when it comes to automotive and respond in layman's terms as much as possible. For affordability reasons I need to repair this myself, but I am learning as I go.

    2010 Prius
    157k miles

    Error codes:
    P0A80 (OBD2-permanent/Replace hybrid battery pack)
    P0A0D (Hybrid Engine/high voltage system interlock circuit high)
    C1259 (ABS/HV system regeneration malfunction)
    C1310 (ABS/malfunction in hv system)

    I have checked all 28 cells and they all measure between 7.2v-7.8v.
    I have removed all tarnish from the bus bar and it looks like new.

    Is there something else I need to do to check the HV battery? So far, it seems to be in good shape. Should I try replacing the ECU? Other thoughts or ideas?
     
  2. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,379
    3,238
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    P0A0D (Hybrid Engine/high voltage system interlock circuit high)

    You have not properly inserted the orange service plug
    it's a three step process.
    insert
    swing up 90 degrees
    sling stringt down until it clicks.

    Rookie mistake. extremely common.
     
    m.wynn and Raytheeagle like this.
  3. Mendel Leisk

    Mendel Leisk EGR Fanatic

    Joined:
    Oct 17, 2010
    56,675
    39,222
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring

    Just from what I've read here: isn't that way too much variation? (n)
     
  4. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,379
    3,238
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    Depends on how they got the readings.
    I assume the voltage readings were taken by hand.
    Easy to incorrectly read the voltages by that much.
     
  5. Rodriguezintexas

    Rodriguezintexas New Member

    Joined:
    Jun 15, 2017
    8
    0
    0
    Location:
    Wylie, TX
    Vehicle:
    2010 Prius
    Model:
    Base
    Thank you, Ericbecky. That did the trick for clearing everything bit P0A80!

    Actually, I cleared all the codes and disconnected the auxiliary battery to reset the computer. The car seems to run fine and the "check hybrid system" light went off. However, the code still appears after running the diagnostic.

    My thoughts:
    1. The code is labeled as *permanent* when it appears in the diagnostic. Is it possible we have solved the problem by cleaning the bus bars, but the code needs to be cleared a different way than through my simple diagnostic device?

    2. The code could be valid, but hasn't caused the warning light to appear on the dash, yet. The battery is fine, but the ECU needs to be replaced.

    3. I have checked the voltage of the cells and all read fine, but I haven't checked the amp hours, nor do I know how to do so. Could this be a problem?

    4. There is something else I am missing altogether.

    5. The battery just needs to be replaced.I can get my hands on a refurbished one oretty cheap, but the volts in the refurb don't read as high as mine, so I don't want to go this route unless I know for sure mine is shot.
     
  6. Rodriguezintexas

    Rodriguezintexas New Member

    Joined:
    Jun 15, 2017
    8
    0
    0
    Location:
    Wylie, TX
    Vehicle:
    2010 Prius
    Model:
    Base
    Yes, they were taken by hand, cell by cell, using a multimeter.
     
  7. Rodriguezintexas

    Rodriguezintexas New Member

    Joined:
    Jun 15, 2017
    8
    0
    0
    Location:
    Wylie, TX
    Vehicle:
    2010 Prius
    Model:
    Base
    Also, I have checked them the times, twice with the bus bar on and once with the bus bar off. It was pretty consistent every time.
     
  8. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,379
    3,238
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    Did you always have the leads and battery terminal correspond?

    Positive lead to positive terminal.
    Negative lead to negative terminal.
     
  9. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,379
    3,238
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    Also you need to watch the battery blocks live while under load.

    Perhaps there are issues there?

    What voltages is the car showing when under load. When charging car or discharging.

    Need and Elm 327 Bluetooth reader in conjuctionwith Torque app. Or some other tools to see data live.
     
  10. Rodriguezintexas

    Rodriguezintexas New Member

    Joined:
    Jun 15, 2017
    8
    0
    0
    Location:
    Wylie, TX
    Vehicle:
    2010 Prius
    Model:
    Base
    Yes, I was careful about that.
     
  11. Rodriguezintexas

    Rodriguezintexas New Member

    Joined:
    Jun 15, 2017
    8
    0
    0
    Location:
    Wylie, TX
    Vehicle:
    2010 Prius
    Model:
    Base
    Sorry, I misspoke. All the cells measure between 7.72 and 7.80.

    I don't know how to test it live, and as a novice, am pretty intimidated about the idea. What is the process using the device you mentioned?
     
  12. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,379
    3,238
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    You actually don't need to "drive" per se.
    Basically "powerbrake" and watch the block voltages.

    Car on.
    Parking brake engaged.
    Foot on brake.
    Put car in drive, leaving foot on brake.
    Put other foot on accelerator to rev the car engine. This will fill up the battery.

    While this is going on see if there are any anomalies with cell block voltages.

    Use an elm 327 Bluetooth OBDII scanner in conjunction with the Torque Pro app and an Android device.

    Set Torque Pro up so you can watch block voltages.

    Feel free to call if you want to discuss on the phone. Sometimes it is easier than me typing out things.
     
    Robert Holt likes this.
  13. Rodriguezintexas

    Rodriguezintexas New Member

    Joined:
    Jun 15, 2017
    8
    0
    0
    Location:
    Wylie, TX
    Vehicle:
    2010 Prius
    Model:
    Base
    The Elm 327 should arrive tomorrow. I will get back to both of you then. I cannot thank you enough for walking me through this.
     
  14. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,379
    3,238
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    Please be careful when powerbraking. Be sure keep your foot on the brake.
    For extra safety you may want to park where there aren't any objects in front of you.

    You can download the Torque Pro app now and set up your custom screens before the elm device arrives.
     
  15. Former Member 68813

    Former Member 68813 Senior Member

    Joined:
    Oct 3, 2010
    3,524
    981
    8
    Location:
    US
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Isn't the procedure for checking health under load by reversing again barrier/brakes?
     
  16. Rodriguezintexas

    Rodriguezintexas New Member

    Joined:
    Jun 15, 2017
    8
    0
    0
    Location:
    Wylie, TX
    Vehicle:
    2010 Prius
    Model:
    Base
    Here are my results.

    I should mention there is often a "stutter" upon take off. Screenshot_2017-06-19-11-05-35.jpeg Screenshot_2017-06-19-11-05-38.jpeg Screenshot_2017-06-19-11-06-03.jpeg Screenshot_2017-06-19-13-06-15.jpeg
     
  17. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
    4,379
    3,238
    1
    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    Looks like battery levels are not consistent.

    There is nearly a 1v difference between the highest and the lowest. The will not like that amount of variance.
     
  18. Jakemathews

    Jakemathews New Member

    Joined:
    Aug 14, 2019
    22
    4
    0
    Location:
    Buena park ca
    Vehicle:
    2012 Prius
    Model:
    Four
    Did you find a solution to this yet
     
  19. AsianDriver

    AsianDriver New Member

    Joined:
    Aug 9, 2019
    11
    2
    0
    Location:
    Houston
    Vehicle:
    2010 Prius
    Model:
    III
    I got the same problem. Waiting to see what you come up with as to the solution. Thanks