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How to tell if the Hybrid battery is doing ok or not?

Discussion in 'Generation 1 Prius Discussion' started by OperaPixie, Jun 25, 2012.

  1. OperaPixie

    OperaPixie New Member

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    South Pasadena, CA
    Vehicle:
    2002 Prius
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    N/A
    Hi there,
    I bought a 2002 Prius about 2.5 years ago now. I love my car. And until last summer, had no problems with it at all. But as my kids & I were driving out of Yosemite Valley, the Hybrid Engine light came on and I freaked out. Got it to a dealer, can't remember now (a year later) what the part was that had to be replaced, but it was only around $350 instead of being the hybrid battery itself (thankfully). A couple of days prior to this incident, we'd been driving around in the mountains near Yosemite, in very hot weather, and had all the power just "drop" out all of a sudden, and I saw that the level indicators on the dash were almost at the empty mark. We chugged along at about 6 mph uphill for about 10 minutes and then the power just "magically" came back and we had no other issues until that light came on. I actually hadn't even thought of that power drop again until the light came on.

    Regardless, the car has run just fine ever since, but I'm now at about 106,000 miles on the car and am worried about needing to replace the hybrid battery at some point (I still owe some money on this car - more than the battery would cost new). Is there any way to easily (and cheaply) do a check-up on the battery to see if I'm looking at needing a replacement sooner than later?

    I don't know if it's related, but I recently replaced my tires and the mileage dropped considerably. It's slowly begun to inch back up a bit (now I'm averaging around 42.2 mpg), but it hasn't returned to the previous norm of between 45-47 mpg.

    In any case, I love my car, am *not* terribly mechanically inclined (but am willing to try just about anything), and will not be in a position any time soon to replace it. I would love to know some tips for keeping it running at optimum, and how to protect it from battery death.

    Thanks in advance.

    ~Laura
     
  2. john1701a

    john1701a Prius Guru

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    2017 Prius Prime
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    Welcome to the forum.

    Your $350 of work may have been a variety of things. The 12-volt battery only lasts so long. That might have needed replacement. The throttle might have needed cleaning as well. There's always the possibility of fluids needing topping off or replacing.

    As for the tires, regardless of type, new ones will always cause a MPG drop. After a few thousand miles, they'll wear down to a point where they roll better. It's a normal break-in thing we all experience. The tires themselves may be an issue. Make sure the PSI isn't too low. That will impair MPG. The type of tire will too, a non-LRR or something with really aggressive tread won't be as efficient.

    At just 106,000 miles, the hybrid battery should be fine for awhile still.
     
  3. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Prime Plus


    The key to understanding is having instrumentation. You might want to consider getting a ScanGauge II and learning how to program in some key, XGAUGEs. This will let you monitor the health and status as well as read out any codes.

    Bob Wilson
     
  4. john1701a

    john1701a Prius Guru

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    Prime Advanced
    I second that. The educational info gleened from that alone is well worth it. You'd surprised how much can be learned about the inner workings of the system by seeing a handful of values while you drive. And if you ever do have an engine-code throw, being able to know what the heck actually happened prior to bringing it to the dealer is enough to pay for the device itself... especially if you question whether the situation was a fluke. Reset the light yourself, then carefully observe what happens following that.

    Long story short, consider some type of aftermarket gauge.

    Heck, just RPM and coolant-temp alone gives you an appreciate for the hybrid system.