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Warning - Key battery low

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by vday, Nov 14, 2012.

  1. AHetaFan

    AHetaFan Member

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    I wish. Maybe the message is a feature of the "Plug-in Advanced" model I have :)
     
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  2. AHetaFan

    AHetaFan Member

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    I decided to get a 5 pack of batteries off ebay. That seems to be the least expensive solution. I'll just putting batteries in as needed to keep the meaningless message away. :)
     
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  3. bisco

    bisco cookie crumbler

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    have you ever tested the voltage, before and after?
     
  4. AHetaFan

    AHetaFan Member

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    I just tested the battery I took out. My battery tester set for 3 volt lithium button cell which has red and green zones shows it in the green. My digital meter shows 2.91 volts. The new battery I put in measures 3.049 volts. I'm not getting the Key battery low message with the new battery installed.

    The one I took out like the one I just put in was purchased from my Toyota dealer and I think both were in Interstate brand packaging. The one I took out has Japanese like symbols on the battery where the brand should be. The new battery says Panasonic brand on it.

    I bought Eveready brand on ebay as my spares.
     
  5. bisco

    bisco cookie crumbler

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    a good battery should measure 3.3 volts. but that may not be the problem. could a button be stuck? does it happen with both fobs?
     
  6. AHetaFan

    AHetaFan Member

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    A 1632 battery is a 3 volt battery. What battery number or brand are you using which measures 3.3 volt?
    As far as I can tell no button is stuck they all do what they should when pressed.

    I only use one of the fobs and have not tried the other. The other fob came with a Panasonic 3 volt 1632 like the one I just installed in the fob I use. I could try switching fobs and put the old battery I just took out in it to see what happens with the message.
     
    #66 AHetaFan, Jun 29, 2017
    Last edited: Jun 29, 2017
  7. bisco

    bisco cookie crumbler

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    all batteries measure about 10% more than the nominal rating when new. for instance, a 12v measures around 13 volts. the devices they power won't work well, when they fall near the nominal rating. for instance, when your prius 12 volt gets close to 12 volts, the computers can start acting funny.
     
  8. AHetaFan

    AHetaFan Member

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    Is that true for button cells? I have yet to test a 1632 that measures over 3 volt new. Panasonic measures 3 volt new. My new Eveready 1632 good to 2025 with 2016 copyright date on the package arrived and they also measure 3 volt. If you know of a brand that measures 3.3 I'll buy some to get the extra time without the key battery low message.
     
  9. bisco

    bisco cookie crumbler

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    i think so, i usually get duracell. i'll check one to see.
     
  10. bisco

    bisco cookie crumbler

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    i just opened my fob and tested the battery. panasonic, i think original, but not positive. 3.03 volts.
     
  11. AHetaFan

    AHetaFan Member

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    Thanks. To see if the fob could be my problem, I'm going to use my second fob with the used battery I took out and see if I get the key battery low message.
     
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  12. AHetaFan

    AHetaFan Member

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    I get the key battery low message with my other fob also. I hate tossing out batteries that are working perfectly but I guess there is no choice. I'm just going to have to put in a new battery if I want the annoying message to go away.
     
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  13. bisco

    bisco cookie crumbler

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    next time you need a battery, spend the 3 bucks on a duracell and measure the voltage just for kicks.
     
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  14. AHetaFan

    AHetaFan Member

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    I have a bunch of Evereadys now but If I remember I might do that. A lithium Duracell shouldn't leak.
    (I used to buy AA and AAA Duracells in bulk and use them up in a year but due to Alkaline leakage damage I stopped buying Duracells and mostly buy lithium batteries in bulk now. No more problem with damage from leaking batteries.)
     
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  15. bikes4u

    bikes4u Member

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    I am having same problem now. I cleaned up the inside of the fob and cleaned the battery. Battery brand new. Did you find a solution?


    Posted via the PriusChat mobile app.
     
  16. Mendel Leisk

    Mendel Leisk Senior Member

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    Might still be the battery: check the voltage on the battery, might be stale? Or a cheapie, counterfeit?

    I've found there's not a lot of difference in the voltage, between the brand new and when I get that warning. The new might read 3.1, and the old one 2.9 or 3.0.
     
  17. Robert Holt

    Robert Holt Senior Member

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    Agree that cheap, knock-off batteries can be a problem. I bought mine from an Amazon vendor, but read all the reviews of several different vendors before finding a Panasonic version that the reviewers were reasonably certain was made in Japan.
     
  18. Grit

    Grit Senior Member

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    I bought the cheapest bulk on ebay, it was a Sony 6 pack. Each battery last only 6 months, got what I paid for.
     
  19. Mendel Leisk

    Mendel Leisk Senior Member

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    I buy them a couple at a time, brand name through London Drugs or Walmart. Forget but close to $10 for the pair? They last maybe 3 years. Not sure who's ahead, lol. Less wear-and-tear on the fob anyway.