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Check Hybrid Battery

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by prius@noob, Oct 21, 2023.

  1. prius@noob

    prius@noob Junior Member

    Joined:
    Apr 6, 2022
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    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    Hello everyone! It's been a while since I last checked in. I apologize for my absence. After encountering some recurring issues last year following the head gasket repair on my Prius, I decided to retire the car and bought another one to serve as my daily driver. (Prev thread: Head Gasket Replacement on Gen 3 prius | PriusChat)

    I had been postponing the sale of the Prius to Carvana with the intent of transforming it into a project car. The plan was to address all its issues, replace suspension components, give it a fresh coat of paint, and more. Unfortunately, due to financial constraints, this project has been put on hold. As a result, the car has been parked in a lot since June this year, patiently waiting for its makeover.

    In June, I began to notice that my car needed to be jump-started every time I attempted to use it. After diagnosing the issue, I realized that I needed to replace the 12V battery. This replacement was done today. However, when I tried to start the car after the battery replacement, a message popped up on the screen saying, "check hybrid system."

    I turned the car off and decided to recheck the new battery installation. During this inspection, I noticed that I had forgotten to connect a cable that should have been attached to a metal bar. After connecting this cable, I attempted to start the car once again, only to find that the "check hybrid system" error persisted.
    In an attempt to resolve this issue, I also tried resetting the errors by unplugging the white cable located near the fuses. Additionally, I experimented with putting the car in maintenance mode to initiate the internal combustion engine (ICE). Unfortunately, none of these actions seemed to resolve the problem.

    At this point, I'm inclined to believe that the issue might be related to the hybrid battery itself. The symptoms I'm experiencing are similar to those described by other hybrid vehicle owners. I encountered a similar error and check engine light approximately a year ago, a few weeks after I had replaced the head gasket. Back then, I managed to temporarily resolve the issue by unplugging the white wire. However, it resurfaced after about 200-300 miles, prompting me to repeat the process. This time, it only provided a brief respite of 20-30 miles, leading me to give up on this car.

    Now, I am determined to fix the car once and for all. However, following the replacement of the 12V battery today, the car refused to start at all, even after removing the white cable for a few minutes. I was able to start the car and drive a couple of miles back in June before I parked it where it currently is. Now, after putting in a 12V battery I’m getting this persistent message and it cannot be reset

    It appears that I may need to address both the issue with the hybrid battery and the previously experienced chain tensioner/chain/solenoid error. Here's pretty much where I ended my tinkering with prius Head Gasket Replacement on Gen 3 prius | Page 5 | PriusChat). My plan is to first tackle the hybrid battery problem and subsequently relocate the car to a friend's garage to address the chain tensioner issue.

    I've identified a YouTube video for replacing the hybrid battery that I intend to use as a guide (Replace hybrid battery). My preference is to replace only the faulty cells rather than purchasing an entire set. Can you recommend where I can acquire these cells at a reasonable cost? I also plan to obtain or borrow an OBD code reader from AutoZone to identify the number of faulty cells. Does this approach seem reasonable to you?
    As always, I am immensely grateful in advance for any assistance and guidance provided. Thank you!

    PS: Formatted with ChatGPT, please ignore the overt language :|
     
  2. JohnPrius3005

    JohnPrius3005 Active Member

    Joined:
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    Location:
    California and Hawaii
    Vehicle:
    2004 Prius
    Model:
    II
    Here are a few suggestions of items you might need:
    digital voltmeter
    12V battery charger
    HV battery grid charger
    techstream
    replacement HV battery

    All can be bought or built quite cheaply, except the HV bat. If you put in some effort you should be able to find a HV bat from a wrecked Prius at a junkyard. The junkyard guys know the value of these, so the effort will be finding an ok guy at a junkyard but St Louis is a big place.

    You're in for a lengthy, challenging, learning experience!

    Good luck.
     
  3. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
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    Location:
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    Vehicle:
    2012 Prius v wagon
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    Three
    I think ChatGPT confused the issue.

    First, to be clear, the issue you are working on above is with your old “replaced hg” Prius that was parked in June? And you are trying to get it running simply to sell to Carvana?
     
  4. Grit

    Grit Senior Member

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    Vehicle:
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    Player 2 has entered the tournament!!!
     
  5. PriusCamper

    PriusCamper Senior Member

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    Vehicle:
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    Two
    There's nothing wrong with your hybrid battery... The problem is Toyota's antiquated battery chemistry/refusal to embrace lithium because it has less proprietary profitability. It's why they're further behind than every other major automaker when it comes to the transition to EV.

    Basically your 1980's battery chemistry, aka: NiMH has a self discharge problem and once they're a decade old and sit without charging for a long time they tend to self-discharge at different rates so your pack has lost its charge and each block of modules is showing the voltages are no longer balanced so you got the related warning lights.

    The solution is a high voltage trickle charger offered by Maxx Volts or Hybrid Automotive. Or you can build your own: Build Hybrid Battery Maintenance Gear For Under $100 | PriusChat

    Once your pack is charged and balanced it will be fine and will have more years of life ahead of it...

    As for your previous interest in making this a project car, perhaps it being too expensive is because of prices for paint jobs for cars are ridiculous these days? And perhaps if you could lower that cost the rest of the costs would be manageable, especially if you look at how much you can sell it for on the west coast.

    In terms of the engine, there's multiple problems with Gen3 engines that are eliminated with a used Gen4 engine swap and there's a guy south of you in Oklahoma who will do a swap in your driveway for $1500 in one day and he probably has a high voltage trickle charger (if not I'll loan him one).

    So potentially you could get this car sold for its highest potential value for less than $3K...

    If that interests you, message: Drew Griffin: 405-696-9828 about his engine swap schedule and tips for finding your Gen4 replacement engine.
     
    #5 PriusCamper, Oct 21, 2023
    Last edited: Oct 22, 2023
  6. prius@noob

    prius@noob Junior Member

    Joined:
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    Location:
    Saint Louis
    Vehicle:
    2011 Prius
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    III
    No, the head gasket replacement went fine. The issues started cascading after the replacement and when I posted the error codes and follow up pics on the previous thread, a user recommended replacing the chain and tensioner. So once I figure out the Hybrid Battery and am able to drive, will resume working on the other issues that might crop up.

    I'm still in 2 minds if I want to sell. I am simply trying to get it into a running condition while I decide what I'd like to do with it.
     
  7. prius@noob

    prius@noob Junior Member

    Joined:
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    Location:
    Saint Louis
    Vehicle:
    2011 Prius
    Model:
    III
    Interesting read! Will look more into the charger, hopefully I can loan it from some mechanics near me who specialize in hybrid cars? Or hire their services?

    As for gen4 replacement, I'd like to see if I can still get it running. Thanks for the contact, will seek assistance if it's too big a job.
     
  8. gsabsa

    gsabsa New Member

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    Location:
    Oregon
    Vehicle:
    2010 Prius
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    Four
    Are you sure the replacement 12 volt battery is good. We were sold a dud once.
     
  9. MrPete

    MrPete Active Member

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    Location:
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    Vehicle:
    2011 Prius
    Model:
    Two
    A few thoughts:

    1) SImplest: "Check Hybrid System" doesn't go away by itself in my experience. Cheapest reliable way to clear it that I've found it OBD2 dongle and Torque Pro app.

    2) Don't need to go all the way to a Gen4 engine. My 2015 Gen3 swap (thanks, Hybrid Pit in Buena Park CA!) is working great. AFAIK they did fix the piston/ring issues by 2015.

    3) Lithium has its own issues of course. A quick read through the winter driving advice of the Norway Tesla Owners Club (tocn.no) is quite eye opening!
    - If the battery gets below 30C, all charge current goes into warming the battery.
    - A battery at 0C (eg sat outside in your workplace parking lot all day) can require several hours of warming before ANY charge is added.
    - (And we've all heard about Li battery fires, dangers of full discharge, etc.)