strange thing, turn on highlight then get 47mpg !!

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by prius-I-like-you, Sep 23, 2012.

  1. prius-I-like-you

    prius-I-like-you New Member

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    first I try fight to smart key fob and seek help in forum. They tell check 12v battery. so I test battery in last 3 ~4 days and check 10 more time.

    If I stop car , all voltage is normal. acc is 12v; IG ( not ready ) is 12v; IG ( ready ) is 14v.

    The strange thing is push gas hard(like race driver and unload every thing: light; AC or CDplayer ) then 12v battery drop to 13.4v ( don't go back 14v). I drive 20 mile and got 40 mpg. :(
    I turn on high light. 12v battery go back 14v !!! I turn off light, 12v battery drop to 13.4v. o_O I drive 20 mile and got 47 mpg with light on. :censored:

    what happen in my prius ?
     
    #1 prius-I-like-you, Sep 23, 2012
  2. uart

    uart Senior Member

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    That (13.4V) is fairly normal p-i-l-y. :) I often get that too, and you don't need to drive "like a race driver" for this to happen. The Prius seems to have a two stage charging system that normally charges the battery at around 14.0 volts, but under certain conditions will reduce that to around 13.4 volts.

    I'm not 100% certain of all the conditions it requires to enter that mode. It seems to require about 20 to 30 minutes of driving, and there may also be a minimum temperature limit, before it happens. Also, if you turn the A/C or fans on it will pop straight back to 14 volts.

    BTW. This thread appears to be almost completely unrelated to its title? :confused:
     
    #2 uart, Sep 24, 2012
  3. prius-I-like-you

    prius-I-like-you New Member

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    I am newb . I only know driver and change tire . I misthink I find some secret .
     
    #3 prius-I-like-you, Sep 24, 2012
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