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"The 12v battery starts the car" no, it doesn't.

Discussion in 'Gen 2 Prius Main Forum' started by Prius92, Aug 5, 2024.

  1. Prius92

    Prius92 Active Member

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    I've gotten into a couple arguments with "hybrid experts" on reddit, and yesterday when I went to a local hybrid shop to get a new cell, ran into the same issue.

    Who came up with this BS?

    Sure, the 12v battery "turns on" the car. But the 12v battery does NOT START the car.

    It's painfully obvious if you look at the transmission. There's no separate high amperage lead set for 12 volts.

    If you look at the inverter, there is one high amp 12v connection, but this is for charging the 12v battery itself.

    The OEM 12v battery itself is only 325 cold cranking amps, which is really small for a modern car. (Yes, I know aftermarket batteries have more CCA, around 410) Now stop and think of all the extra electrical things the Prius has that most non-hybrids at the time did not. Also this 325CCA is WITH the smart key system,

    3 electric coolant pumps, about twice as many computers, a 12v operated auxiliary heater system, 12v brake accumulator, etc. Some models also had navigation which would of used a bit of power as the system is based on a DVD disc drive.

    I think the people who state "the 12v battery starts the car" have never actually studies Toyota's hybrid drive system.

    Take a look at the size of a regular car starter motor's windings and then look at the massive windings in the Prius MG1 motor which starts the car.

    [​IMG]

    [​IMG]
     
    #1 Prius92, Aug 5, 2024
  2. Tombukt2

    Tombukt2 Senior Member

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    They don't really care they're just arguing regular car talk points from click and clack tap it or what have you. No matter but yeah the motor generator access the starter because anytime the Prius is moving forward the reciprocating mass is turning as in the Pistons are going up and down that sort of thing there's a lot people don't understand about the Prius oh well certainly not worth getting in an argument in a bar about or any of that kind of crap. Let them go out and look for the starter etc etc oh well Why is the engine running when you're backing up if the transmission isn't used to back you up only the electric motors are because the battery needs to be popped off and you know whatever. It doesn't really matter what they understand. In today's climate it's not worth arguing with anybody about anything because everything can be whatever they say it is because they said so that's the world we live in now it's facts are non-existent until somebody gets killed or blown up.
     
    #2 Tombukt2, Aug 5, 2024
    BiomedO1 likes this.
  3. dolj

    dolj Senior Member

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    You are arguing semantics.

    It probably would be helpful for you to differentiate in your mind the difference between starting the car and starting the gas engine.

    If you think of it like that yes, the 12 V battery starts the car and the HV battery starts the gas engine.

    It is not that big of a deal
     
    #3 dolj, Aug 5, 2024
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  4. bisco

    bisco cookie crumbler

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    someone on the internets was wrong?
     
    #4 bisco, Aug 5, 2024
  5. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Well, the Prius won't start without the 12 volt, so maybe semantics? Obviously not involved in the heavy lifting, but if ain't there...

    People argue that if the Prius 12 volt battery measures low cranking amps (significantly below spec), all is good, since "it's not involved in cranking". I'd counter that even so, any 12 volt battery showing low CCA is on it's way out, regardless of it's use.
     
    #5 Mendel Leisk, Aug 5, 2024
  6. BiomedO1

    BiomedO1 Senior Member

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    Don't forget about the "alternative truth":(o_O:rolleyes::D:LOL::ROFLMAO::sick:
     
    #6 BiomedO1, Aug 5, 2024
    Last edited: Aug 5, 2024
  7. ColoradoBoo

    ColoradoBoo Senior Member

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    lol....totally true! And I tell people who love to argue and fight to get a Reddit account....seems like major brawls going on constantly!!
     
    #7 ColoradoBoo, Aug 5, 2024
  8. highmilesgarage

    highmilesgarage Active Member

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    if you post it 100x, it will become the truth..

    btw, did you ask yourself "if the car will start if there's no 12v battery"?
     
    #8 highmilesgarage, Aug 5, 2024
  9. BiomedO1

    BiomedO1 Senior Member

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    Sorry, Had a brain fart. I meant to say: Alternative Fact.

    It might be a dead worm in my brain, but I'm too afraid to get it scanned - It may be just an empty cavern. o_O:oops:
     
    #9 BiomedO1, Aug 6, 2024
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