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2007 Dr. Prius Results are ???

Discussion in 'Gen 2 Prius Technical Discussion' started by Bigflank, Nov 26, 2020.

  1. Bigflank

    Bigflank New Member

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    I have a Gen 2 Prius from 2007 with just over 120,000mi on it. I recently got slammed with a bunch of bad mechanical news and it will cost around $2000 to fix everything. After 13 years, I figure I should see how my hybrid battery is doing before investing that much money into my car.

    Bought BAFX Products Bluetooth OBDII Reader and the Dr. Prius app. Ran the Life Expectancy test 4 times. It was around 35F outside. Here are the results (images attached):
    1st test: 43.92%
    2nd test: 54.94%
    3rd test: 61.71%
    4th test: 68.24%

    I think the first test is garbage as I don't think the engine was warmed up enough, but the other three are pretty wild. Plus there's the overall trend of increasing capacity with time, which I'm guessing is due to temperature?

    The amperage sometimes (maybe 5% of the time) spiked or dropped before returning to nominal (spiking to around 8.0 Amps then returning to around 5.5 Amps, or dropping to around 4.0 Amps before returning), requiring sometimes major adjustments to the power I was using. Less adjustments were needed for the later tests than the earlier tests. (This is why 3/4 of the tests have the "battery overdrew power for more than 20 sec" alert.)

    What do folks think? Does my battery have several years of life left, or is it on it's last legs? Are there additional tests I should try running?
    Screenshot_20201126-123000_Dr Prius Test 1.jpg Screenshot_20201126-124145_Dr Prius Test 2.jpg Screenshot_20201126-125353_Dr Prius Test 3.jpg Screenshot_20201126-131051_Dr Prius Test 4.jpg
     
  2. edthefox5

    edthefox5 Senior Member

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    Welcome to PC.

    Your battery is 13 years old. If its dropping to one or two purple bar real fast like at a drive through or light or you have see a red bar before its on its last legs.
    The fact that it has so low miles is another knock against it.
    So yeah i can almost guarantee you that right after you drop $2000 on the car the battery will fail.

    Your new here drill around on this site the other G2 forums you aill see almost all of us G2 owners are having issues with the hybrid battery including myself. I bought a new after market battery after propping up my original for 3 years with a battery charger made to rejuvenate hybrid battery's.
     
  3. rjparker

    rjparker Tu Humilde Sirviente

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    First, run the test four more times and you will up to 93%. That's quite an app, maybe Dorman will buy it to make their refurb batteries last longer.

    I think there is a reason Toyota hv batteries usually last ten years or 150,000 miles. They were designed to meet early California warranty requirements without breaking the bank in warranty expenses and without overbuilding them at higher initial costs.

    Now Toyota offers everyone 10 years 150,000 since they have twenty years of history on them. They know how to make them last that long.

    There is little doubt that cooler climates are easier on air cooled batteries than are hotter climates. So the odds are in your favor for another two or three years at 9k miles per year, especially if no fast discharge cycles at idle are yet happening. It is interesting to note that all EVs except the Leaf have liquid cooling to extend their lifetimes and to allow higher charge discharge rates.

    Meanwhile your Dr Prius results seem to represent a data set that shows battery life expectancy tests are still an art rather than a science. It's far easier to prove a battery is dead than proactively declare it is weakening.
     
  4. mr_guy_mann

    mr_guy_mann Senior Member

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    The app's test results show that your battery isn't dead. That's about all you can tell for certain. It could read 95% and still have a module die next month. If you don't like risk then dump the car. Spending money on repairs today for an older high-tech car doesn't guarantee that you won't have problems later.

    Posted via the PriusChat mobile app.
     
  5. alftoy

    alftoy Senior Member

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    $2000 in repairs at a dealer, local mechanic or for parts? What are the repairs?
     
  6. Bigflank

    Bigflank New Member

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    Touring
    Thanks, everyone. Appreciate the welcome, @edthefox5! I've noticed the battery at two bars a couple times at lights, but haven't noticed whether it's dropping from full to that while I'm sitting there. I'll try to look for that.

    Sounds like I have one person saying the battery is likely about to crap the bed, one person saying it likely is still good, and one person saying they have no idea. Dang. Not exactly the unanimous verdict I was hoping for. Still, I appreciate the input!

    $2000 in repairs, including parts and labor. Most issues are fairly standard, but they all clobbered me at once:
    • Need new tires (+ balance + alignment)
    • Left rear strut spring needs replacement. It's missing the last coil, so the car sits about 3/4" lower on that side than the other. Still have suspension, though. (I could in theory replace it myself, though I'd still need to bring it in for alignment afterwards.)
    • Need new disk brakes
    • Need new brake rotors
    • Need new TPMS sensor. (Not a necessity, but it is annoying having the pressure sensor light on all the time.)
    The new tires are the most urgent need: I'm having to refill two of the tires every two days due to leaks. (Got bad over the summer. Didn't notice because I've been working remote due to COVID.) I'm not experiencing any brake issues, but replacing them and the rotors is nonetheless pressing for safety reasons.

    So, does that change anyone's thoughts? Or if anyone else would like to chime in, I'm all ears!

    Thanks again, folks.
     
  7. alftoy

    alftoy Senior Member

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