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Prius won't start...HELP

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by pandeyrajiv, Feb 2, 2012.

  1. Patrick Wong

    Patrick Wong DIY Enthusiast

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    With the car IG-OFF, turn on the headlights and see how bright they are. If dim, the battery is discharged. Or use a digital multimeter to measure voltage across the 12V battery. A new, fully-charged AGM battery will measure 13VDC. A voltage measurement of 12VDC or less means the battery is discharged.

    Then, if the battery is more than four years old, replace with new. If younger than four years, try charging it with a battery charger intended for AGM batteries, 4A charging position, overnight.

    There is no alternator. The DC/DC converter in the inverter serves that role. To test it, make the Prius READY and measure voltage across the 12V battery with a digital multimeter. The voltage reading should be ~13.8VDC. If much lower, the DC/DC converter is bad or the DC/DC fusible link has blown, typically due to a botched jumpstart.
     
    Dan D. likes this.
  2. Heather Cain

    Heather Cain Junior Member

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    typically due to a botched jumpstart.[/QUOTE]

    What exactly would a WRONG jumpstart look like? I've been jumping it in the front. But I noticed the back battery exposed and uncovered when I got it back. I guessed someone had jumped it from the back.

    Basically I already bought a new 12v, but I don't want to install it until I know 100% that's the issue. And my mechanic says my 12v is fine.
     
  3. bisco

    bisco cookie crumbler

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    a wrong jump start is mixing up the positive and negative. doesn't matter if it's the front or back, it will blow the big fuse and potentially fry the inverter, which can be quite pricey.
     
  4. Heather Cain

    Heather Cain Junior Member

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    Ok, cool, I would hope to high hell that ANY mechanic can locate both + - signals on a battery. I doubt they messed up the pos/neg.
     
  5. bisco

    bisco cookie crumbler

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    when i had body work done on my '04, they somehow managed to drain the hybrid battery, which starts the engine. so they had to bring in a special toyota charger, which at that time were scarce. one per region i believe.
     
  6. Heather Cain

    Heather Cain Junior Member

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    oof. i'm now very concerned this is my problem. Problem is. I can't take it too far right now, as it's NOT street legal. The closest dealer isn't even an option. I have yet to start the frame repair, but I'm concerned that if I finish getting all the body done then I'm going to find out it's need a new hybrid battery or some such horribleness.
     
  7. Heather Cain

    Heather Cain Junior Member

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    I'm also wondering if I can take action against this first body shop that it was in. Really there should have never been a reason it died in the first place, but I'm guess it did so, because of the DOOR or they did something to damage the system.
     
  8. exstudent

    exstudent Senior Member

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    An open door, open hatch, interior map light left on, SKS fob left inside the car or near the car, will drain the 12V accessory battery. This heavy drain may possibly decrease the overall life expectancy of the 12V battery. However, if a drained 12V battery is properly recharged w/ an AGM compatible battery (ideally), the 12V battery should be good to go for more years. Most here seem to have gotten 4-8 years on 12V batteries. This service item can be as low as $140 for a non-Toyota battery (Bosch, Exide), or $160-$175 (Toyota; but you'll have to find a large % off parts coupon, or get the parts department to try to match a Toyota dealers on-line price).

    Would be tough to prove any damage from that first repair shop, unless they botched a jump start and didn't properly undo the damage they caused.

    It sounds like you are in possession of the car, but need to drive the vehicle over to the body shop for frame work repair?
     
  9. dolj

    dolj Senior Member

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    People must compare like for like, so don't go comparing prices of normal flooded lead/acid starter batteries with AGM batteries.

    The OEM is actually good value for what it is, and when it is TrueStart badged has a pro-rated 84 month guarantee.

    It is probably too late for the OP, but just to provide balance for future readers of this thread, the Optima is not a superior product to the OEM battery. If you get a good one they are ok.

    Capacity: OEM (for SKS) 45 aH | Optima: 39 aH
    Price: OEM $183 | Optima: OEM $195 (inc SH)

    There are many people on PC recently that have reported their new Optima to be semi discharged on arrival and others that report their new Optimas dying prematurely. More sad stories of people trying to get warranty and after sales service from online sellers.

    Another AGM option: Exide FP-AGM51JIS

    The OEM battery, just for reference, is YUASA S46B24R-GS

    I don't wish to rain on anyone's parade, but I hope that help someone in the future.
     
  10. Patrick Wong

    Patrick Wong DIY Enthusiast

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    If the jumpstart was reversed, the DC/DC 100A fusible link will blow. This link is located in the fusible link assembly. The fusible link assembly is a 5" long plastic box with a clear cover, and can be found in the main relay/fuse box next to the inverter.

    If the DC/DC fusible link is found to be defective, then the DC/DC converter also may have been destroyed which would require replacing the inverter. The DC/DC converter serves the same role as the alternator in conventional vehicles. However the inverter as a new part costs into the four-digits compared to an alternator which typically is priced in three-digits. So you would probably want a used inverter to be installed.

    Assuming the DC/DC 100A fusible link is good, you can make the Prius READY, and measure voltage across the 12V battery. It should be around ~13.8V which shows the DC/DC converter is working. If much lower, the DC/DC converter has failed.

    If the fusible link is blown, you would have to replace the fusible link assembly. Then measure voltage as described above to determine whether the DC/DC converter is good or bad.

    My post #21 provided two easy methods enabling you to form your own opinion about how good or bad your 12V battery is.
     
    #30 Patrick Wong, Apr 19, 2015
    Last edited: Apr 19, 2015
  11. andrewclaus

    andrewclaus Active Member

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    Post deleted.