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Load testing 12V battery

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Crain, Sep 10, 2015.

  1. Crain

    Crain Junior Member

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    I'm just getting back into working on cars namely my Prius. I have some tools I used back in the day but am reluctant to use them on the Prius. A case in point ...a battery tester that puts a load on the battery. You clamp it to the battery push the button and it puts a load on the battery and shows the battery's condition. This type of tester is still available. My question is "can I use it to test the Prius 12V battery?" I think I would have to remove the battery cables to isolate the battery from the elec. system??? My Prius is a 2009 with the original battery and I think with winter coming on its time to replace it
    Thanks Don
     
    #1 Crain, Sep 10, 2015
  2. JC91006

    JC91006 Senior Member

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    Save yourself the time in testing it and just replace it. It's 6 years old.
     
    #2 JC91006, Sep 10, 2015
  3. Mendel Leisk

    Mendel Leisk Senior Member

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    I found this video a week or so back. The guy uses several devices to test a battery, including a traditional load tester. It shows good condition with all. Then he uses a new device, to test CCA, not so good. Not sure of the validity, but anyway.

     
    #3 Mendel Leisk, Sep 10, 2015
  4. mikefocke

    mikefocke Prius v Three 2012, Avalon 2011

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    Do you disconnect the battery leads from the car before doing the testing?

    With a traditional load tester?

    With this new marvel?
     
    #4 mikefocke, Sep 10, 2015
  5. edthefox5

    edthefox5 Senior Member

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    I have that old school load tester your referring to. Basically a big toaster element and a meter. I find its much more accurate and benign to monitor its behavior on a decent battery charger.
    If the battery charges up pretty fast and goes to 0 zero current thats usually a pretty good sign. If it struggles to charge up quickly at 2 amp rate and takes forever to show zero current draw thats a pretty good sign its worn out and sulphated.

    The problem is this little agm when it fails tends to fail fast. Best to just replace and not have to worry about getting stuck in a snow storm and exposing the car to the dreaded jump start.
     
    #5 edthefox5, Sep 10, 2015
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