2015 Prius Two dead as soon as I power it off

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by AdamXX, Aug 29, 2021.

Tags:
  1. AdamXX

    AdamXX New Member

    Joined:
    Aug 29, 2021
    11
    2
    0
    Location:
    MA
    Vehicle:
    2015 Prius
    Model:
    Two
    A few days ago, I found my Prius two was dead - when I opened the door, there was no buzz, no light, complete dark on the panel; when I pressed the power button, zero response with everything that should light up just remained off.

    I thought I accidentally drained the battery by leaving the light on, so I went ahead and jump-started it with no trouble. After I drove it around for 15 miles, parked it in front of my garage, and pressed the power button to turn it off, the panel and all the lights just went totally dark immediately and it won't start again (same as before I jump-started it). I jump-started it again and drove a bit longer, but the same problem remained.

    I jump-started it the third time and measured the 12v battery (in the trunk) that showed a healthy 14.4v voltage. I measured the jump-start (positive) terminal in the main fuse box and it showed ZERO voltage. Then I shut the car off and checked a few fuses which were all good.

    Has anyone experienced a similar problem or have any idea what I should check next? Is it normal for the jump-start terminal to have zero voltage?

    Thank you very much for your inputs!
     
  2. AdamXX

    AdamXX New Member

    Joined:
    Aug 29, 2021
    11
    2
    0
    Location:
    MA
    Vehicle:
    2015 Prius
    Model:
    Two
    Ok, now it is completely dead --- I could not even jump start it as before. Can anyone help?
     
  3. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    5,302
    3,737
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    git r new batiry.
     
  4. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    14,634
    10,279
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    The times you jumped it, you were using the jump terminal in front?

    I would carefully check the connections to the battery in back: the positive clamp on the battery post, the negative clamp on the battery post, the connection where the negative wire bolts to the body, and the fuse built into the positive clamp.

    If you find the fuse is open, find out what's wrong in that cable running up to the front before replacing the fuse.
     
    privilege likes this.
  5. Mendel Leisk

    Mendel Leisk Sand Pounder

    Joined:
    Oct 17, 2010
    45,528
    32,507
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Taking a drive in a car with near-dead battery is not a “get out of jail free” card.
     
    privilege likes this.
  6. AdamXX

    AdamXX New Member

    Joined:
    Aug 29, 2021
    11
    2
    0
    Location:
    MA
    Vehicle:
    2015 Prius
    Model:
    Two
    Yes, I was using the jump terminal in front.

    Thanks for the advices! Where is the "fuse built into the positive clamp"? I've never noticed this before.
     
  7. rjparker

    rjparker Senior Member

    Joined:
    Jun 6, 2008
    4,039
    2,118
    2
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    I will guess your 12v battery is totally dead and is dragging down your jump battery. Could be corrosion on the cables around the battery or the negative body end. Check those items.

    Then its time to measure voltages with the system off. Start at the battery. Should be 12v-12.7v. Then measure the engine fuse box incoming 12v white cable 1E location. Should be the same as the battery, if zero then check 140a fuse on positive battery terminal. Then visually check the fuse box 125a located under the top section. Finally measure voltage fed by the 125a fuse. See diagram and pics. Any fuse in the top right of the diagram is fed by the 125a fuse. Any voltage on the interior fuse box is fed by the 125a.
    39C2AB98-3675-42EC-8030-C02A8FDF39C1.jpeg


    FC609BC5-C364-478C-AA71-B836AAC33581.jpeg 79C62163-0B98-47A0-A7A4-6F920A2B00CA.jpeg
     
    #7 rjparker, Aug 30, 2021
    Last edited: Aug 30, 2021
    burrito likes this.
  8. AdamXX

    AdamXX New Member

    Joined:
    Aug 29, 2021
    11
    2
    0
    Location:
    MA
    Vehicle:
    2015 Prius
    Model:
    Two
    I found it, and confirmed this fuse is good.

    My bad, the negative pin of my multi-meter was not grounded correctly. The jump terminal does have voltage.
     
    #8 AdamXX, Aug 30, 2021
    Last edited by a moderator: Aug 30, 2021
  9. AdamXX

    AdamXX New Member

    Joined:
    Aug 29, 2021
    11
    2
    0
    Location:
    MA
    Vehicle:
    2015 Prius
    Model:
    Two
    The wiring diagram is really helpful, thank you Sir!

    (I was measuring in an incorrect way) The jump terminal does have the same voltage as the battery terminal, but at 2.49v. However, this is a battery I replaced last summer for $150:cry:.

    Now, the question is, should I buy another battery just to try? If the new battery still does not work and all self-diagnosis options exhausted, how can I jump-start the car myself (then drive) without paying 100$ to have it towed to a garage?
     
  10. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    14,634
    10,279
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    The part of the clamp that kind of drapes over the side of the battery. It's like Dalí painted a battery clamp.
     
    AdamXX and Mendel Leisk like this.
  11. rjparker

    rjparker Senior Member

    Joined:
    Jun 6, 2008
    4,039
    2,118
    2
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    That battery is dead and buried, 98.9%. But it should still have a warranty so take it out and have the seller attempt to raise the dead. If he can't you should get a prorated reduced price new battery.

    Do not pass go, do not collect $200.
     
    AdamXX likes this.
  12. saltdiscus

    saltdiscus Member

    Joined:
    Oct 29, 2016
    198
    88
    0
    Location:
    US
    Vehicle:
    2014 Prius
    Model:
    Two
    Yeah warranty if not dealer will tow and put new battery if you buy from them.
     
  13. Maarten28

    Maarten28 Active Member

    Joined:
    Jul 13, 2014
    414
    207
    1
    Location:
    Netherlands
    Vehicle:
    2011 Prius
    Model:
    Three
    Of course, because the inverter is giving 14.4 V to charge the battery. So the healty you refer to is to the inverter, not the battery. You can't infer battery health from this.
     
    Mendel Leisk and privilege like this.
  14. privilege

    privilege Active Member

    Joined:
    Mar 17, 2021
    501
    127
    0
    Location:
    Birmingham
    Vehicle:
    2011 Prius
    Model:
    Three
    it's a really good idea to inspect the cables for corrosion. if they're corroded, they will reduce the batteries efficiency and cause starting problems, both in high (regular car's) starting and low (Prius) amperage starting/charging.

    given your description of the running voltage, the charging system is good but the 12v battery has expired
     
    Grit likes this.
  15. AdamXX

    AdamXX New Member

    Joined:
    Aug 29, 2021
    11
    2
    0
    Location:
    MA
    Vehicle:
    2015 Prius
    Model:
    Two
    This makes total sense, thank you!
     
  16. AdamXX

    AdamXX New Member

    Joined:
    Aug 29, 2021
    11
    2
    0
    Location:
    MA
    Vehicle:
    2015 Prius
    Model:
    Two
    Thank you for the recommendation! I did inspect the cables and they look clean.
     
    privilege likes this.
  17. AdamXX

    AdamXX New Member

    Joined:
    Aug 29, 2021
    11
    2
    0
    Location:
    MA
    Vehicle:
    2015 Prius
    Model:
    Two
    Thanks! I bought the battery from Advance Auto Part, so luckily it is still under waranty. I will take the battery out and bring it to the store for a replacement. Cannot believe the battery would die only after one year's light use.
     
  18. rjparker

    rjparker Senior Member

    Joined:
    Jun 6, 2008
    4,039
    2,118
    2
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    What is sometimes missed is the car has a continuous drain on the battery even when shutdown. This is known as a parasitic load. Normally it is very low, maybe 25 ma, but even that can discharge the battery over a period of weeks if the car is not run or is only operated for a mile or two each week.

    However there can be excessive parasitic load from 50 ma (ma is thousands of an amp) to several amps. Usually caused by the rear hatch slightly ajar or aftermarket equipment sucking power all the time. Sometimes an obd2 device. In your case it was probably a bump on the road that caused an internal battery connection to fail.
     
    #18 rjparker, Aug 31, 2021
    Last edited: Aug 31, 2021
  19. AdamXX

    AdamXX New Member

    Joined:
    Aug 29, 2021
    11
    2
    0
    Location:
    MA
    Vehicle:
    2015 Prius
    Model:
    Two
    I took the battery to AdvnceAutoParts today. They checked it to confirm the battery is dead, then they gave me a replacement. The car came back to life after I installed the new battery. Thank you everyone for the help! This is a great forum.

    Just for the sake of discussion, will parasitic drain or cable/terminal corrosion damage the battery and make it die? I am asking because I want to make sure my problem was purely a battery problem and not anything else.

    Now I am having a new problem - all the windows (except the driver side) are not operable with buttons on the driver side door, but they are still functional with the button on their respective doors. This problem didn't exist before the battery went bad. Any ideas?
     
  20. Higgins909

    Higgins909 Member

    Joined:
    Apr 15, 2018
    134
    40
    2
    Location:
    Texas
    Vehicle:
    2010 Prius
    Model:
    III
    I think it was earlier this year I had to replace my 12v. I just took the old one to test at Autozone and bought a $200 battery from them. Only had a 3 year warranty. The battery I replaced was a Toyota True Start and it had a 84 month warranty and lasted 90 something months. Something like that. I have no idea how much the True Start battery was. I assumed it was more and don't know how much longer my car will last.
     
Loading...