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Prius crank but won't start

Discussion in 'Generation 1 Prius Discussion' started by MasterTin, May 25, 2016.

  1. MasterTin

    MasterTin New Member

    Joined:
    May 25, 2016
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    Location:
    Seattle
    Vehicle:
    2001 Prius
    Model:
    ----USA----
    Hi all,

    Notes:
    • Car is a 2001 Toyota Prius
    • Car had a dead 12V battery but I had a portable jump pack I always use to start the car no problem
    • I had the car in the shop to do some body repairs and I'm guessing the mechanic might have reversed jump the car as the car was working just fine (by jumping) before I took it in to the body shop.
    • When I jump the car, the HV battery will crank the motor for about a second, the engine tries to start but stutters out.
    • When I try to jump again after 10 seconds, the HV battery will crank the motor but now just a split second and the engine barely cranks and doesn't start.
    • When I try to jump again after 10 more seconds, the HV battery will NOT crank the motor and nothing turns.
    • The car dash screen shows that the HV battery is at about 25%.
    • There is no engine codes.
    What I've done:
    • Replaced the main 100A fuse by the 12V battery
    • Disconnected and reconnected the main HV battery flip switch
    I'm down to my last option as the Toyota dealership was useless and wanted to charge for a new 12V battery ($500) and diagnostics ($150) before looking at why the engine won't crank.

    Thanks!
     
  2. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    Location:
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    Vehicle:
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    Model:
    Four
    Why not put a new 12V battery in yourself?
     
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  3. DRACO

    DRACO Member

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    Location:
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    Vehicle:
    2002 Prius
    Model:
    One
    +1 ^^^
     
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  4. greasemonkey007

    greasemonkey007 Active Member

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    Location:
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    Vehicle:
    2006 Prius
    Model:
    N/A
    Especially when you can buy a Toyota battery on ebay for $200 or less and spend 10 minutes putting it in.
     
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  5. MasterTin

    MasterTin New Member

    Joined:
    May 25, 2016
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    Location:
    Seattle
    Vehicle:
    2001 Prius
    Model:
    ----USA----
    Maybe I didn't explain it well enough. My apologies. I didn't replace the 12V battery because I was able to jump before even though the 12V battery was dead. Now even with a jump the car wont' start (with another good working 12V battery). If I could get the car to finally start, I will go and buy a new 12V battery as soon as possible.

    Q: I thought the HV battery was responsible for actually cranking the engine? Not the 12V.
     
  6. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Location:
    Huntsville AL
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    Correct. Once the traction battery gets low enough, you're SOL until it is charged back. Now there are two options:
    • Mythical Toyota charger - there is a floating, undocumented connector that can hook up to this Toyota charger so they can recharge the traction battery.
    • Pull it and charge it - the simplest and most straight forward approach. It also gives a chance to inspect the buss bars and clean out the crap.
      • If you take this approach, consider installing an extra connector that has four, high-voltage (aka., 300V) diodes that support external charging of the two banks. Diodes are inside the case. This would let you 'tickle charge' the traction battery to bring the SOC to 80% (or higher) at night. When you start in the morning, this stored charge will let you drive on EV while the engine warms up. With solar panels on the deck behind the rear seat, you can even tickle charge away from a plug.
    Bob Wilson
     
  7. greasemonkey007

    greasemonkey007 Active Member

    Joined:
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    Location:
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    Vehicle:
    2006 Prius
    Model:
    N/A
    My apologies for not reading the original post thoroughly. It does sound like the HV battery is run down. For around $350 or $400 you can buy a grid charger from Hybrid Automotive posted here on Prius Chat. Then you can charge up your battery and keep it balanced from time to time. You can even purchase the stuff to do a full recondition if you'd like.