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2005 Prius mad sad buzzing noises while parked, 12V dead?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by vttym, Feb 8, 2013.

  1. vttym

    vttym Junior Member

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    Have been driving my Prius with no issue all week. I leave the car home and take my wife's vehicle, while she drives it today without incident. I come home and hear the car making some strange beeping noise (NOT the anti-theft alarm, different). I hop into the car and try to start it, and the check engine and ABS lights come on for a second before other lights in the spedometer area kinda half come on. The gear indicator comes on and has boxes blinking on all of the letters.

    The MFD never comes on.

    From what I'm reading, it appears to be the 12V battery dying. The car has 150k miles and I have never replaced the battery, so from what I'm reading, it seems I was way overdue for this.

    I ordered the optima battery and instruction kit from elearnaid.com.

    I have no tools for checking voltage, or for hooking up a battery to retain memory settings when making the change. What settings do I stand to lose, and what additional steps will I need to take after making the battery change to make sure everything is OK? Do I run any risks with not hooking up a backup battery to retain memory settings? Any other recommendations, or will the included directions be sufficient for me? Am I going to have additional problems because it seems I let the 12V battery die completely? I still can see the clock when I push the ignition button, so there's SOME juice left.

    Sorry, this came out of left field and I want to make sure I'm not missing anything.
     
  2. vttym

    vttym Junior Member

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    Would something like this work for retaining settings?

    Noco Settings Keeper | Product Details | Pep Boys

    Most of the stuff I read mentioned a 12V battery as backup, this seems to work off a 9V. It shows up when I'm looking for Prius battery information on their search.
     
  3. V8Cobrakid

    V8Cobrakid Green Handyman

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    use a lantern battery or lawnmower battery or anything else to keep the voltage there. (at one time i used a "dead" 18v power tool battery that was down to 13v and dropping)

    if the system is that low, it's possible to lose your settings anyway.

    Id say that product won't work.. the cigarette lighters are switched.. car has to be on for them to work. If you're waiting for the battery to arrive, simply turn the car on by jump cables, disconnect the old and connect the new. the car doesn't use the 12v when it's actually on.

    this would be a good time to get a jump box as a just in case of emergency type of thing. specially if you're afriad to help any friends or family members with a jump start.

    best way to send voltage strait to the system is by the + jump terminal under the hood (top of black fuse box under red cap) and by grounding the - on the strut bolt above the fuse box. that bypasses a lot of things and should allow you to start up easier.

    btw.. all you lose is the time, your current mpg and radio stations.... it's not too bad....
     
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  4. dorunron

    dorunron Senior Member

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    One other thing that is lost, the power window has to be reinitialized. After the battery change, simply lower the window halfway, then raise it up and hold the switch up for a few seconds. The window will then be initialized. Changing the battery in a Prius is not that bad. Follow the instructions that come with the yellow top and you should have no problems.

    You really don't need the 12 volt backup to save the settings unless you are worried about losing radio presets, and having the trip odometers reset to 0 along with having to reset the clock.

    Tip for you: When you go to put the top screw for the traction battery vent back in, use some tape or grease to help hold the screw in the socket on the extension, as it is hard to see. When you do the job, you will understand what I am talking about. The screw is hidden behind the carpet and it holds the plastic duct in place along with another screw. It seems that most of us have found that is the tricky part to the whole thing.

    Ron
     
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  5. vttym

    vttym Junior Member

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    Awesome ... thanks for the tips, folks - looks like it won't be too much hassle for the switch and losing the settings. Appreciate the peace of mind.

    Now just to actually .. you know.. do it.

    Been a while since I've been on the forums.. seems after reading the maintenance section that I might need to swing the car over to a dealer and have them do a few things. I have been doing basic oil change/rotation since 120k, so might be due for a more in depth maintenance stop.

    Thanks again!
     
  6. dorunron

    dorunron Senior Member

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    FWIW, I changed our 12 volt in a little over an hour. I used two wrenches, two sockets, one ratchet, a few extension, a little grease, a small hammer, a flat blade screwdriver and a drop light to help illuminate the work area. The size of the tools were 10MM and 12MM (both wrenches and sockets). The sockets and extensions were 3/8" drive. A deep socket will help with one of the nuts on the battery hold down, however you can do the job with just the wrench.

    Before you do anything, look closely at everything before you start. If you are slightly mechanically inclined, you should find no problems doing the job. Be certain to disconnect the negative first and reconnect it last. I found it easier to remove the bolt on the end of the cable that attaches to the body rather than trying to loosen the negative terminal at the battery. There is not a lot of room with the battery set in place. Also, if you are not aware, the battery will be under the floor in the right rear (passenger side) of the hatchback area. If you don't save settings, you may have to power up twice to get the car into Ready mode. Also, when you first power up, the fuel gage will read empty, but will reset itself in a few seconds.

    If you need more help, start a conversation with me and I can help you. The job is very easy. The hardest part is that top screw that I mentioned as it is hard to see and tricky to get to.

    Ron
     
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  7. vttym

    vttym Junior Member

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    As an update, I was able to make the change with ease. I was a little worried when I was briefly stumped on the first real step (loosening the bolt on the negative terminal - didn't have a 10mm wrench with me at the time, just sockets!) .. once I got a wrench, all proceeded as planned.

    Thanks for the help and reassurance!
     
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  8. dorunron

    dorunron Senior Member

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    Based on what I read in your post, it sounds like you were able to change the 12 volt battery with little to no problems. I am glad to hear that you got through it with minimal problems or trouble.

    I hope the information I posted did help you. If you found it was of help to you, you can click like on the post's if you so choose.

    Good luck to you and enjoy your Prius.

    Ron