Dead 2006 Prius

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Hadit, Apr 14, 2021.

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  1. Hadit

    Hadit Junior Member

    Joined:
    Apr 14, 2021
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    Location:
    Endwell NY 13760
    Vehicle:
    2006 Prius
    Model:
    One
    Now I'm even more confused!
    I assumed that the dead car was either the fob or the 12V battery. Changed the key fob battery, even though the red light was blinking. (didn't know what that meant until now)
    Couldn't open the back door from inside. Then saw in the manual that you can jump start it from the front. Problem was, it said to "Turn off the hybrid system" first. What does that mean? Especially when the car is dead! So that confused me, and now Richard S. says the 12V doesn't start the engine anyway, so what exactly am I jumping, so to speak? :sneaky: And then what? Can I charge the 12V from the front, as well? I have a charger, can I just leave it on? Of course it may not even be the battery ... I hope I'm not confusing everyone as much as I am! Thanks
     
    #1 Hadit, Apr 14, 2021
  2. mr_guy_mann

    mr_guy_mann Senior Member

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    Location:
    NJ-USA
    Vehicle:
    2006 Prius
    Model:
    Four
    Ok, the 12V battery supplies power to all the computers (ecu's) that control everything on the car- if that battery is bad or discharged (dead) then the car won't work.

    Normally when you press the power button (with foot on the brake) the various computers will "boot up". If they have no problems then one ecu will allow relays to connect the High Voltage battery to the inverter assembly. The inverter handles power flow back and forth between the 2 electric motors in the transmission and the HV battery. (It also has a voltage converter that supplies around 14V to charge the 12V battery and power all lights, accessories, and other low voltage stuff).

    When the gasoline engine is needed, the inverter uses power from the HV battery to spin the MG1 motor- which goes through gears to rotate the engine. There is no "starter".

    Whenever the car is "on" and has the green "ready" light- that is the hybrid system it powered up and the converter is supplying 14V. They don't want you trying to "jump start" or boost the Prius under that condition (which it don't need anyway). Any other state (such as being "dead") is ok to try and boost.

    Ideally you would measure voltage at the underhood jump point with a digital multimeter, and if it's low (fully charged with everything off is 12.6V or so) then connect a charger to recharge slowly.

    Posted via the PriusChat mobile app.
     
    #2 mr_guy_mann, Apr 14, 2021
    DaviDino and Hadit like this.
  3. Hadit

    Hadit Junior Member

    Joined:
    Apr 14, 2021
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    Location:
    Endwell NY 13760
    Vehicle:
    2006 Prius
    Model:
    One
    Thank You Mr_guy_Mann!
    My charger shows level of charge when hooked up, so I shouldn't need to use a voltmeter, right? And I can slow charge from under hood, or do I have to connect to the battery itself? Sorry to pester!
     
    #3 Hadit, Apr 14, 2021
  4. rjparker

    rjparker Tu Humilde Sirviente

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    Jun 6, 2008
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    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    Charge slow or whatever from the front, much safer for the car than the back where confusion can lead to burnt up parts if the battery is charged in reverse or installed backward. Some will say use an advanced charger like a four stage battery tender in case confusion causes you to leave a single stage old school charger on for days at a time.
    Battery tener jr features.jpeg
     
    #4 rjparker, Apr 14, 2021
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