1. Attachments are working again! Check out this thread for more details and to report any other bugs.

I really messed up

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by wek, Jun 17, 2019.

  1. wek

    wek Junior Member

    Joined:
    Jul 17, 2012
    13
    0
    0
    Location:
    Durango, Colo
    Vehicle:
    2005 Prius
    Model:
    N/A
    Hi
    Well, It should of been easy, but when installing my new starter battery on my 05 prius I hooked up the positive first then tried to connect the negative to the body or the car and sparks flew. Now nothing is responding. I hope it's just a fuse, but don't know which one. Any help here would be appreciated.
     
  2. edthefox5

    edthefox5 Senior Member

    Joined:
    Jul 25, 2007
    10,096
    4,795
    0
    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    Most likely the dome fuse in the kick panel by left knee.

    But ......turn on the headlights and see if they work. If not you most likely smoked the main 100 amp fuse in the engine fuse box the one under clear plastic. That’s not good.

    Highly unlikely those sparks blew the fuse. Sure it’s not in backwards?

    To lurkers this method of installation is not how to do it. There are 2 connectors on the battery positive mounting Assy. One connector is big black wire the other is thin black wire. Compress the white plastic clip lock on the connector and pull them both out one by one that disconnects the battery from the car. No sparks no issues.
    Reinstall after bolting battery back in.
     
    bisco likes this.
  3. JayMikey

    JayMikey New Member

    Joined:
    Jun 6, 2019
    6
    0
    0
    Location:
    Ohio
    Vehicle:
    2007 Prius
    Model:
    N/A
    Is this also the procedure to follow anytime you want to temporarily disconnect 12v from the car for performing work? In so many other places I've read to just unscrew the negative cable from the body. Does the way you mentioned achieve the same desired effect without the risk of sparking/blowing a fuse?
     
  4. edthefox5

    edthefox5 Senior Member

    Joined:
    Jul 25, 2007
    10,096
    4,795
    0
    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    Yes jay it does. It completely disconnects the 12 volt battery from the car no sparks no smoke no regrets. Recently had to do it a few times when my combo meter kept going bad and could not shut the car off. So I left the little red plastic cover off. Its still off.

    Its a little bit difficult to figure out how the clip releases. You depress the lock tab and then gently pull the wire out. If the wire does not come right out the clip is not yet released.When you plug it back in it clicks back in.

    The big black wire is the wire that is bolted to the front jump point in the front under hood fuse box. Its the main battery 12 volt B+ cable to the car.
     
    Raytheeagle and JayMikey like this.
  5. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,461
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Since the car is inoperable, is it possible that you reversed the battery polarity?

    As Ed suggested, see if the headlights turn on. Will the dome light in the passenger cabin turn on?
     
  6. wek

    wek Junior Member

    Joined:
    Jul 17, 2012
    13
    0
    0
    Location:
    Durango, Colo
    Vehicle:
    2005 Prius
    Model:
    N/A
    Hey
    Thanks for the response. The batt was in correctly. It is still dead and I'm at a loss on the 100amp fuse. I see a clear fuse box location under the hood. Hard to tell if it's blown. I see a fuse on the positive terminal. Could that fuse be blown?
     
  7. wek

    wek Junior Member

    Joined:
    Jul 17, 2012
    13
    0
    0
    Location:
    Durango, Colo
    Vehicle:
    2005 Prius
    Model:
    N/A
    Well, it starts when I jump start it. Yea! bad news is it won't start again unless I jump it. Seems like a relay switch?? Any ideas to save me from the dealer. They will want to install new hybrid battery. Thanks
     
  8. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,474
    38,106
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Maybe just the 12 volt battery is bad? Or am I missing something. Once it's jump started, it runs normally, you can drive it?

    Check the voltage on the 12 volt for starters (with a digital mulimeter). And then maybe do an electronic load test, see what the verdict is.
     
  9. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,461
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Where are you connecting the jump cables - at the battery or at the jumpstart point next to the inverter?

    If you can jump the car successfully at the jumpstart point but not at the battery, then you probably have to replace the 120A MAIN fuse at the battery positive terminal.
     
    Mendel Leisk likes this.
  10. edthefox5

    edthefox5 Senior Member

    Joined:
    Jul 25, 2007
    10,096
    4,795
    0
    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    Hey pat doesn’t the jump point go through that 120 fuse also?
     
  11. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,461
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    No
     
  12. cyberpriusII

    cyberpriusII Prodigyplace says I'm Super Kris

    Joined:
    Oct 1, 2009
    1,135
    1,560
    0
    Location:
    Iowa
    Vehicle:
    2008 Prius
    Model:
    N/A
    I'm lost!!

    What else is new?

    So, when I replaced my 12v, I connected the positive cable to the new battery and then connected the negative to the point on the car body and got lots of sparks, which scared me, but did no damage.

    I really did not understand ETF5's way of doing the connection that he detailed earlier in this thread, but that method avoids risk and the sparking, which seriously came close to making me lose bladder control when I did it 7 years ago?? :whistle:
    kris
     
  13. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,474
    38,106
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I always heard negative is the first to disconnect, last to reconnect, is safer. Don't much care to understand the why's and wherefores, above my pay scale.
     
    Raytheeagle and cyberpriusII like this.
  14. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,474
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    You get paid:whistle:?
     
    Mendel Leisk likes this.
  15. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,461
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    The explanation is simple.

    If you were to short a battery terminal to body ground with the wrench you could cause lots of damage if you shorted the positive terminal (while the negative terminal is already connected to ground.)

    If the negative terminal is not connected then there is no harm in shorting the positive terminal to ground.

    Hence, disconnect the negative side first, and reconnect that side last.
     
    Mendel Leisk and jerrymildred like this.
  16. wek

    wek Junior Member

    Joined:
    Jul 17, 2012
    13
    0
    0
    Location:
    Durango, Colo
    Vehicle:
    2005 Prius
    Model:
    N/A
    Then I wonder what went wrong when I changed out the starter battery, connecting positive first then the sparks when I tried to connect the negative to the body of the vehicle?
     
  17. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,461
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    A small amount of sparking is normal. If you find that the 120A fuse at the positive terminal has blown then you did something abnormal.
     
    Mendel Leisk and jerrymildred like this.
  18. jerrymildred

    jerrymildred Senior Member

    Joined:
    Oct 28, 2016
    11,490
    14,095
    0
    Location:
    Tampa, FL
    Vehicle:
    2017 Prius
    Model:
    Two
    I was just about to chime in, but @Patrick Wong beat me to it. I've always disconnected the negative first and connected it last for the reasons he explained. I've always gotten a little bit of a spark because there's always something low power that runs whenever there's power. And it's never been a problem, even on the five Prii I own or have owned.

    What is alarming is when you're wiring up a 480 volt three phase motor contactor and some meathead millwright starts a weld right behind you the instant you put a wire in its terminal. Doesn't matter that you know the panel is dead, the blinding flash of light rules out all thinking. You jump a mile and may need new underwear.
     
    Mendel Leisk likes this.
  19. Skibob

    Skibob Senior Member

    Joined:
    Sep 14, 2018
    2,912
    1,494
    0
    Location:
    Northern California
    Vehicle:
    2006 Prius
    Model:
    N/A
    Yes that big box the positive battery terminal is bolted to is a fuseable link (fuse). Part # 82620-47040. Check your battery on the terminals then on the jump points, they should be similar. If the jump points are 0 and you have power at the battery then that fuseable link could be the problem.
     
  20. wek

    wek Junior Member

    Joined:
    Jul 17, 2012
    13
    0
    0
    Location:
    Durango, Colo
    Vehicle:
    2005 Prius
    Model:
    N/A
    Well it finally took the dealer mechanic to find that it was the ground side of the 12v battery was not secured. this caused an excessive voltage drop not allowing battery voltage to vehicle control module. No blown 100 amp fuse. So now it starts and runs but the triangle of death symbol and a bunch of others appear. The codes say replace hybrid battery and more
    Funny how a Prius hybrid battery goes bad fast. I do have 150K on it
    I see there are $800 hybrid replacement batteries on Amazon. With enough U-tube videos is this something, someone can do themselves??? It seems like the only cost effective way to save this 2005 vehicle. The stealer want $4K to fix it