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How sophisticated is the Prius' battery monitor?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Rich12, Jan 19, 2014.

  1. Rich12

    Rich12 Member

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    Curious if the Prius MFD uses a simple voltage-drop monitor for the HV battery SOC or there are more sophisticated methods to test?
     
  2. Britprius

    Britprius Senior Member

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    The monitor uses coulomb counting and voltage monitoring to calculate the state of charge. (sophisticated)

    John (Britprius)
     
  3. Britprius

    Britprius Senior Member

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    Duplicate post

    John (Britprius)
     
  4. jadziasman

    jadziasman Prius owner emeritus

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    You should do what I just did a couple of days ago. I bought a cheap android phone ($22) that I don't use as a phone. I downloaded the torque app for android and bought an ELM327 OBDII bluetooth adapter from Ebay for $10.

    I now have access to engine rpm, engine coolant temp, and many other parameters which Toyota did not believe that an average driver would want to see. I also have access to HV battery block voltages, MG1 and MG2 rpm and torque, etc.

    So for less than $40, you can have a monitoring system that is superior to Scangauge II and Ultragauge.
     
    GrumpyCabbie likes this.
  5. nh7o

    nh7o Off grid since 1980

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    And throws battery temperature as well into the mix, if I am not mistaken.