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12v battery

Discussion in 'Newbie Forum' started by Monaco, Feb 2, 2012.

  1. Monaco

    Monaco New Member

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    Just replaced my 12v battery,it went sitting in a parking lot.Had to get a jump start, then went to the nearest dealer and told me that it took a special battery and they would'nt recommend buying one say from sears. So over $300 later I got a new battery,just wanted to let everyone know to do some research when they think there battery is about to go .They usually last about 6 years good luck.
     
  2. F8L

    F8L Protecting Habitat & AG Lands

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    So your saying if you had done the research you would have saved $150 by purchasing the battery (OEM or Optima) and installing it yourself? :)
     
    1 person likes this.
  3. kornkob

    kornkob New Member

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    This is pretty well known here.

    There are better batteries out there than the Toyota battery, incidentally. Also, depsite their protestations, this is a user serviceable part.
     
  4. bisco

    bisco cookie crumbler

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    :welcome: did you get any warning signs before it actually died? i have an 08 that seems to be as strong as the day i bought it. sears probably doesn't carry a replacement, but i doubt a dealer would ever recommend buying anything anywhere else. and yet, there's a whole world of aftermarket parts for savvy shoppers. :)
     
  5. syscon

    syscon Member

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    The standard 12V Prius battery don't have much chance being charged when engine constantly turns off.

    Wouldn't be a good idea to connect small trickle charger 1.5amps overnight?
    I'm sure the battery would last longer.
    My current Optima is 13-years old.
     
  6. F8L

    F8L Protecting Habitat & AG Lands

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    The 12v battery is not getting its power directly from the engine so the engine cycling on and off will not affect its charge rate. Even when the engine is off the bus voltage is still 13.9-14.2v. :)
     
  7. richard schumacher

    richard schumacher shortbus driver

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    F8L is quite right that 12V battery charging is independent of the engine when the car is on ("Ready"), but do note that the 12V battery does not get charged when the car is off. If you make nothing but very short trips the battery can suffer.
     
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  8. hill

    hill High Fiber Member

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    Yep, RS & f8L both said it ... but one more point to nail it down. The ICE starts by way of the monster sized (in comparison to the teeny 12v aux battery) traction pack.

    Sorry your welcoming here is on such a sour note ... things WILL get better.
    :thumb:

    .
     
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  9. J5A

    J5A Active Member

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    Monaco, hope you'll stick around! You'll get lots of great advice...before falling into the hands of the service dept.
     
  10. SDB54

    SDB54 Junior Member

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    First time owner of a 2006, and first with a brand new 12v (not sure what brand)
    I bought the car on Friday, drove for at least 70 miles no problems, car re-started every time I need to after stopping for gas etc. Next morning, it also starts fine. I go to the car wash. After the car wash finished, I was cleaning the windows, etc for no more than 15-20 min. I go to start the car...dead. No lights no nothing. Luckily someone was there to jump the battery. The car started in less than 30 seconds after the portable battery charger was connected. I drove back the place where I bought the car for them to check it out. The moron who put the new battery in didn't tighten down the positive connection, so they tighten it up, we check the multi-display after learning how to get it into diagnostic mode, etc, and it reads 14v. I go about my business for the afternoon/evening and all seems well.

    Drove Sunday for a good while and no problems as I do my errands etc and have to re-start the car a few times.

    I start it up Monday am, drive it to work and leave it with the valet. There are tons of Prius' and other hybrids, so I figure these guys know how to turn the car off etc after they park it etc. The headlights were never on. 6pm comes, they've moved the car since morning and as I approach the car to get ready to go home, the doors are not unlocking. Battery is completely dead again. Luckily someone nearby has a portable charger and in less than 30 seconds the car starts.

    This scenario is kind of freaking me out. You can't even open the rear hatch without crawling into the back seat, taking all the s*** out of the trunk area and manually opening the trunk from inside..... is there a hatch release lever I don't know about somewhere?

    So, being a Prius newb I have a questions. Would the 12v battery eventually die when they moved the car and maybe forgot to turn it off? or would the gas engine kick in over and over until the car ran out of gas? Doesn't seem like that's what happened, but I'm curious.

    The lights were not left on so it wasn't the problem. All doors were closed and locked as far as I could tell. If there were a dome/vanity light was left on, the switch would've been set to whatever it was on Friday/Saturday, so not sure that was the issue. I did leave the phone charger connected to the cig lighter under the dash, but nothing was plugged in as far as a phone, and I had done that the previous 2 nights. As I say I'm not so great with a multi-meter, so no sure where to go from here?

    Sorry for the diary post ; )
     
  11. Skibob

    Skibob Senior Member

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    So the first advice I can offer is to start a new thread if you have a problem rather than hijacking a seven and a half year old one.

    That being said if the car were left in the ready condition it would basically just keep starting the engine to keep the traction battery at a certain level. The 12v would continue charging during this time, just like what happens when the engine is running in a regular car. 12v is charged by the big battery and the inverter, a Prius has no alternator.

    When you were cleaning the inside of the car you probably had the interior lights on and that drained the battery. The battery is rather small, not like a regular car that uses the 12v to start the car. You do not say how long your drive is but it takes quite a few hours to charge the 12v fully. That 14v the car lot guy showed you was the charging voltage, the resting voltage is far more important to know as it tells you the condition of the 12v battery.

    And you can open the hatch with a dead battery. You just have to hook some 12v to the jump points first. Then the hatch will open. Engine running or not.
     
    #11 Skibob, Aug 27, 2019
    Last edited: Aug 27, 2019
  12. GrGramps

    GrGramps Active Member

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    Does this assume the hood was left open? Or have I missed the obvious?
     
  13. Skibob

    Skibob Senior Member

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    You can open the drivers door with the mechanical key in your fob and then pull the hood latch.
     
    #13 Skibob, Aug 27, 2019
    Last edited: Aug 27, 2019
    Mendel Leisk likes this.
  14. SDB54

    SDB54 Junior Member

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    It's certainly possible I drained the 12v battery by having the doors open/interior lights on while cleaning the inside. I'll have to get used to the only having 12v and make sure the interior lights are off next time, unless there's a better way?

    After the guy tightened up the loose battery connection, and we checked what you're saying is "charging voltage", I let it run for maybe 10 minutes, and shut it off. I was on the lot for a good hour after that, waiting for some paperwork. When I started the car to go home, it fired right up. Probably took me 45 minutes to get home. Once home and the car off, I was inside my place maybe 2 hours, getting some gear together to play a music gig that night. I loaded the car, the car fired right up and I drove 1 hour to the gig. The gig was 5 hours, all said and done. At about 1am, the car fired up again no problem and I drove home about 50 minutes, so I assume the battery was re-charged after that?

    Still no clue what happened on Monday at my work parking lot? Either someone left a light on or...

    This morning I turned off the DRL and set the dome lights to be off all the time. I also turned off the smart key feature for the time being. I read that it transmits voltage or such, which allows the doors to unlock when you approach the car.and that car also deplete the 12v battery? Just eliminating a few things, and will slowly bring these things back into the fold and see if I can pinpoint anything. I'm a little freaked out and want to make sure this doesn't happen again anytime soon.

    I did read about being able to jump the battery from the positive connection under the hood etc. I have to say it was a PITA removing stuff from the trunk area and the spare tire cover, tool tray, etc, in order to pop the trunk. Maybe I should get one of those small, portable car chargers and leave it in the car just to be safe. Reading about parasitic battery drainage freaked me out a bit as well, but I'm new to the Prius, so I'll learn to diagnose better, sooner than later : )

    Didn't mean to hijack an old thread, but I guess it did it again...sorry
     
    #14 SDB54, Aug 28, 2019
    Last edited: Aug 28, 2019
  15. Skibob

    Skibob Senior Member

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    You still need to check the resting 12v battery. Lots of threads here telling you how to do it.
     
  16. SDB54

    SDB54 Junior Member

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    Thanks, yes indeed. Don't want to get stuck who knows where, with a dead 12v battery.
     
    #16 SDB54, Aug 29, 2019
    Last edited: Aug 29, 2019