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prius state of charge goes way down

Discussion in 'Gen 2 Prius Main Forum' started by priusguam, Feb 23, 2009.

  1. priusguam

    priusguam Junior Member

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    Before my battery failed the dealer checked mine when I started to see some weird variations and he said it was ok. I think the batteries test ok until they totally go bad then they go fast and dramatically. I hope this isn't going to be a regular thing for lots of Prius' but it seems like this problem is popping up more and more on the forum
     
    Rizzbell likes this.
  2. priusguam

    priusguam Junior Member

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    Update: Car is running great now. No swings in the SOC. Always blue. Rarely green or red. Mileage went up about 2-3 mpg. Dealer said corrosion was found on some of the cells and some of the cells were bad. Not surprised as its super humid and salty here. One day I will have the car in a garage with a dehumidifier.
     
  3. Wolfie52

    Wolfie52 Senior "Jr" Member

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    Call me a nut, but it seems too many (here) obsess about SOC or how their battery is doing. One thing about having a Navigation system is I just keep the map screen on most of the time. Why be anal about if you are getting 51 MPG instead of 48? Your mileage is great--trust me! Or thinking something is wrong with your battery because it is on the second bar? This is how mental illness starts...

    If something is really wrong, you will know it: there are enough warning lights to tell you. I used to be this way about all the POS (and they WERE real POS!) cars I drove when I was 18, 19 and 20. I constantly analyzed every noise, wiggle, shake, click and the smoke coming out the back. The things I worried about never happened!

    This is a form of mental illness! Just drive your car, and STOP ANAL-ylzing all the information. Just turn on the map (or TURN OFF THE MFD if no nav) and turn on some tunes, and RELAX.
     
  4. F8L

    F8L Protecting Habitat & AG Lands

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    I disagree. If the symptoms that they should be ignoring lead to a defective battery then it is best they catch it early in the car's life when it can be repaired for free under warranty. Ignoring the symptoms could lead to an expensive fix if it finally fails hard enough to light up the warning symbolbs on the dashboard. $1,500-$3,000 for a repair that could have been avoided is sad.

    priusguam, As for a $6,000 battery replacement charge...... Let's just say you'd have to have more money than common sense to pay such a fee. The dealership may have put that on your invoice but there is no reason to spend even half that on a simple replacement. Unless of course you are in a different country. :)
     
  5. priusguam

    priusguam Junior Member

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    Just letting you guys know what the invoice said. I do live in Guam which probably included higher than normal shipping charges. They also said they replaced the battery harness which had some corrosion. Either way, they did the right thing and did it for free. You are very right that it is good to catch this early and get it done under warranty. The SOC was a clear indicator that things were wrong. Now it stays in a narrow range and never gets below 50 unless Im parked with the A/C on when it will run the SOC down to 42 to avoid starting the ICE.
     
  6. V8Cobrakid

    V8Cobrakid Green Handyman

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    as the OP has mentioned, my battery also drops during warmup. it always has but it does it a little faster now.

    i have 145,000 miles on my car. 5 years left on warranty.

    my "test" has shown that i can still travel a good distance in EV mode... roughtly a half a mile on flat groud.. probably a mile or so with a slight downhill. my original numbers were better.. but that was with stock wheels....

    i tend to find myself paying attention to the battery draw on my mfd.
     
  7. Rizzbell

    Rizzbell New Member

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    I had similar issues with pickup on my '06 while it was still under warranty. We nicknamed it The Gutless Wonder because it would show 4, 5, 6, bars when you pulled out of your parking spot and for the first couple blocks. Then, usually when pulling onto a major street, it would suddenly be at 1 bar and almost stuttering to move forward. This seemed to happen after it had sat for a bit, at least overnight. After driving a while, it would return to normal charging/recharging fluctuations. I dealt with this daily in all weather and terrain.

    I took it to the dealership well before the 10 year/100,000 mile mark and they, of course, could find no problems. Said they couldn't duplicate my *numerous* experiences.

    Fast forward to 12 years/~120,000 miles, I get the red triangle of death. Since I had attempted to solve this problem while under warranty, I called Toyota to see if they would stand behind their hybrid system, but since the dealership that had blown me off had noted that 'all systems were operational', Toyota told me I was up a creek.

    I ended up pulling the transit battery, testing all modules, and replacing the three that seemed to have dramatically lower charge than the rest and I was able to get rid of the triangle and pass emissions to get my registration renewed. Now the plan is to make a couple repairs and trade this bad boy in for something totally different. I'm done with Prius.

    The point of my story is that if you are experiencing this sudden loss of power, it is not a fluke. It is the first warning sign of cells that cannot hold a charge. If you are under warranty and the dealership cannot or will not identify this problem, go to the next dealership. And the next. Be pushy.

    If you are approaching the end of your hybrid system warranty and you have not had any such issues, I recommend trading in before that safety net is gone.