New OEM 12V shows 11.5V after two months?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by ericspoor, Mar 7, 2019.

  1. Skibob

    Skibob Senior Member

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    Really?
     
  2. ericspoor

    ericspoor Member

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    might be misremembering, but i think the fully-charged battery was installed before cleaning the ground cable and measured 12.8 volts which was higher than it ever had before, then the cable was cleaned and only after was the battery measured with the car in ready. possible it would've measured 14v in ready even without the ground cable cleaned. but idk
     
  3. sam spade 2

    sam spade 2 Senior Member

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    Yes, really.
    What's the point of turning this into an argument ?

    He does not KNOW for sure what the root cause of the problem was........and neither do you.
    The battery might have just worn out.
     
  4. kens97uber171

    kens97uber171 Active Member

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    20 min of driving will probably not fully charge the 12v. You should fully charge that thing. Can get a cheap 12v charger from anywhere. Harbor freight has a nice small 4amp charger and also a bigger one if you want that. It has setting for AGM/Standard 6/12 volts. and even cold temp options if it is cold outside
    Jump starting the battery is not CHARGING the battery. Just giving it a boost enough to start the car.
    BTW it's the Hybrid battery that actually turns the ICE over. The 12V battery only runs the cars electronic systems. And the Prius is very sensitive to a low 12V battery.. all kinds of weird stuff happens.
    Good luck.
    Here is the link to that HF charger

    4 Amp Fully Automatic Microprocessor Controlled Battery Charger/Maintainer

    Posted via the PriusChat mobile app.
     
  5. ericspoor

    ericspoor Member

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    thanks for the help! i ended up getting a 12v charger and fully charged the battery+cleaned up some corrosion on the ground cable and that did the trick. And youre right, a bunch a weird stuff was happening- clock would show a wrong time, odo would switch to km/h, etc.
     
    Mendel Leisk and kens97uber171 like this.
  6. sam spade 2

    sam spade 2 Senior Member

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    I was about to say that I wouldn't trust any of the chargers at HF......but that one might be an exception.
    The Cen-Tech ones are cheap junk.
     
  7. kens97uber171

    kens97uber171 Active Member

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    Agree the old transformer ones are junk.
    These new ones are a high frequency charger.
    I've had good luck so far.

    Posted via the PriusChat mobile app.
     
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