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

Weak Battery Cells

Discussion in 'Gen 4 Prius Technical Discussion' started by A Hussain, Oct 8, 2019.

  1. A Hussain

    A Hussain New Member

    Joined:
    Aug 1, 2019
    15
    4
    0
    Location:
    Pakistan
    Vehicle:
    2016 Prius
    Model:
    IV
    Hi All,
    i have prius 2016 gen 4. i was getting hybrid system malfunction and pre-colision safety error. i did the battery stress test and the result is 92%. however when i see the battery voltage its showing few blocks giving high voltage (pics attached).

    can anyone guide me the real issue, i mean is it a battery problem or something else. incase if it is a battery problem then suggest me is it good to replace the bad cells or entire battery pack.

    Battery Voltage1.jpg

    Battery Voltage.jpg
     
  2. Dxta

    Dxta Senior Member

    Joined:
    Nov 7, 2016
    1,932
    767
    0
    Location:
    Lagos
    Vehicle:
    2008 Prius
    Model:
    II
    I don't think you did performed the load tests as its supposed to. How did you do that?
    All of the modules are supposed to be in the 16.something, and not jump suddenly to 33....volts. If you've the time, opened up the pack cover and check for corrosions on bus bars.

    PS: if no error lights showing on the dash, y worry!?
     
    Prodigyplace likes this.
  3. A Hussain

    A Hussain New Member

    Joined:
    Aug 1, 2019
    15
    4
    0
    Location:
    Pakistan
    Vehicle:
    2016 Prius
    Model:
    IV
    i went to a garage, that guy had a software "Launch". he did stress battery test and the result was 92%. but at the same time same software showing the battery voltage as shown in picture. this i have done yesterday and till now there is no error (the guy did some service/cleaning). however before this i was getting error every second day.
     
  4. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    7,044
    7,587
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    I'm interested more in the "hybrid system malfunction and pre-collision safety error". Wondering if there is some link between the two?

    Do you have access to an OBD2 reader to check for error codes. It could well be something totally separate from battery.

    When I had about 8 or 9 malfunctions flash across my screen soon after I received the car - when the dealer had a look, it was the BRAKE LIGHT SWITCH - had given a single fault. They replace it, and no more malfunctions.
     
  5. A Hussain

    A Hussain New Member

    Joined:
    Aug 1, 2019
    15
    4
    0
    Location:
    Pakistan
    Vehicle:
    2016 Prius
    Model:
    IV
    the torque app on obd2 giving me error code "P1AC0".
     
  6. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

    Joined:
    Nov 1, 2016
    11,801
    11,363
    0
    Location:
    Central Virginia
    Vehicle:
    Other Hybrid
    Model:
    XLE
    If you have the equivalent of a US Trim 4 you have a Lithium Ion battery. Are you sure your testing and measurements are correct for that battery chemistry?
     
  7. A Hussain

    A Hussain New Member

    Joined:
    Aug 1, 2019
    15
    4
    0
    Location:
    Pakistan
    Vehicle:
    2016 Prius
    Model:
    IV
    Its Ni-mH battery and it is Japanese car Prius 2016 4th gen ZVW50 with Safety Plus package.
     
  8. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

    Joined:
    Nov 1, 2016
    11,801
    11,363
    0
    Location:
    Central Virginia
    Vehicle:
    Other Hybrid
    Model:
    XLE
    I am surprised you are already seeing issues. My 2017 with the same battery is still going strong.
    How many kilometers are on the car?

    Are you sure whatever software you are using has been tested to work with Gen 4 Prius? That does not look like Toyota diagnostic software.
     
  9. A Hussain

    A Hussain New Member

    Joined:
    Aug 1, 2019
    15
    4
    0
    Location:
    Pakistan
    Vehicle:
    2016 Prius
    Model:
    IV
    9,000
     
  10. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

    Joined:
    Nov 1, 2016
    11,801
    11,363
    0
    Location:
    Central Virginia
    Vehicle:
    Other Hybrid
    Model:
    XLE
    Battery problems that early would be extremely unlikely and would be anToyota warranty issue here in the US. I have over 30000 miles on my Gen 4 with NiMH battery.

    You mentioned multiple warnings. What is the health of the 12 volt battery? A weak one can give very strange errors when the computers get confused.
     
  11. A Hussain

    A Hussain New Member

    Joined:
    Aug 1, 2019
    15
    4
    0
    Location:
    Pakistan
    Vehicle:
    2016 Prius
    Model:
    IV
    12 volt battery means the main battery in with engine? if you referring that....truly speaking i have not checked that part.
     
  12. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

    Joined:
    Nov 1, 2016
    11,801
    11,363
    0
    Location:
    Central Virginia
    Vehicle:
    Other Hybrid
    Model:
    XLE
    Yes. If it does not charge well & gets too low, the computers can get confused.
     
  13. fotomoto

    fotomoto Senior Member

    Joined:
    Apr 22, 2009
    5,608
    3,788
    0
    Location:
    So. Texas
    Vehicle:
    Other Hybrid
    True but the OP only has 9,000 KM on a potentially 4 year old car. That's a lot of down time and/or very short trips; neither of which are good for battery health so it's possible....

    Yes, check the 12 volt battery's health (load test if possible). Low use is bad for it too.
     
  14. Elektroingenieur

    Elektroingenieur Senior Member

    Joined:
    Jan 8, 2017
    2,515
    3,268
    9
    Location:
    California
    Vehicle:
    2016 Prius
    Model:
    Three Touring
    Blocks 3–7 are supposed to be higher; see my October 2018 posting.
    Use a Toyota Techstream diagnostic system, or equivalent, to read the diagnostic trouble codes (DTCs), and then refer to the troubleshooting procedures for each DTC in the Repair Manual (more info).
     
    #14 Elektroingenieur, Oct 8, 2019
    Last edited by a moderator: Oct 9, 2019
    alanclarkeau and Prodigyplace like this.