Replace 12v Battery?

Discussion in 'Newbie Forum' started by Caleb2007, Jun 30, 2019.

  1. Caleb2007

    Caleb2007 New Member

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    That was actually the very first thing I did when the madness started. I opened up the back and checked the fan. It had a layer of hard dust that didn't seem like it would impede the spinning of the fan. I am wondering if the fan is coming on enough/at all? The one time I have seen it come on as running was one the Torque Pro app at a "1". I don't know know how many speeds it has, but it probably could have been going faster? So the fan itself looked ok. The vent from the cabin does not have a filter and is very dark and windey so I can't really see deep enough to figure out if it is clogged or not. You mentioned being able to adjust the fan speed with the App? (Did you see my attachments?)
     
  2. PriusCamper

    PriusCamper Senior Member

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    Well... Next least expensive fix after hybrid battery fan is pulling pack, getting voltage data & load testing data on a spread sheet and cleaning out all the corrosion... If those high temp readings are accurate one of your 168 cells is still passing the high-amp current but has for the most part failed, just not completely and that's the source of all your heat and warning light problems. Though I'm still unclear if your 12v battery is so far gone all of the rest is just an aberration of a weak 12v, but most likely it's time to replace a module, as well as recondition pack in order to find next bad module after that / increase packs performance. Or go with brand new pack and forget about it being an issue for another 6-10 years...
     
    #42 PriusCamper, Jul 4, 2019
    Last edited: Jul 4, 2019
  3. Mendel Leisk

    Mendel Leisk Titanic Social Director

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    Just for another data point:

    Highest temp I've ever seen (albeit on our 3rd gen) was around 45C (113F). Fan speed then was maybe 4. This was in extreme stop-and-go, hot day.

    Driving on cool evening, easy going, it would settle in around 35C (95F). Fan speed then maybe 1.
     
  4. Caleb2007

    Caleb2007 New Member

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    So, according to Dorman's website, their batteries "have technology that prevents corrosion". Whether or not this is entirely true, I am certainly dubious. However, after only 2 years and 14000 miles, I would like to give them the benefit of the doubt. How reliable was this "test" on the Dr Prius app, and what exactly does it tell me? prius pic.PNG
     
  5. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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  6. Mendel Leisk

    Mendel Leisk Titanic Social Director

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    Nickel plated bus bars?
     
  7. BurkPhoto@aol.com

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    Yes, it is entirely likely your 12-Volt battery is dying. Change it soon. Get the one sold at the parts counter of your Toyota dealer, as it is guaranteed for 7 years (pro-rated, of course). Also, if you haven't changed the spark plugs yet, consider replacing them. The other thing to check is tires... Proper inflation? Correct type?

    I have a couple of 2009s that get the same mileage now as they did when new.
     
  8. PriusCamper

    PriusCamper Senior Member

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    Well... as for special technology to prevent corrosion... It's called di-electric grease and seals the electrical parts so they are not exposed to moisture in the open air, yet still allows electricity to flow, thus limiting the severity of corrosion over time. Issue is that stuff is a mess to work with. I only spray it on bus bars of packs that are brand new and / not going to removed and put into a different car in the future.

    Rebuilt batteries are not brand new and periodic replacement of bad modules every 1-3 years is to be expected and I'm not going to grease up a rebuilt pack if there's a chance the pack will be worked on again by me or some other person that doesn't want to get their hands all greasy and nasty.

    I'm not sure if this is the "technology" Dorman uses or not, but in general they're a dishonest operation selling over-priced rebuilt battery packs as if they were new and nothing could be further from the truth.
     
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  9. PriusCamper

    PriusCamper Senior Member

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    We make jokes about that test on Dr. Prius app... There's not enough of a frame of reference to make sense of yet, especially wen it estimates how much longer the pack will last, which is a highly problematic estimate to make. One thing it does do that's helpful is point to Block #4 as being a problem and that could be the source of a failing cell creating your high temps.
     
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  10. Caleb2007

    Caleb2007 New Member

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    So, I think I'll buy and install a 12v battery on my own, just to eliminate that completely. It probably should get a new one anyways. I'll keep driving it and seeing how it seems. As of right now, its been a week since I had any lights, and my OBD II doesn't get any codes from the car. So I could be worried about nothing. Also, kinda random, but every so often, out of the blue, the volume on the radio will change itself, fluctuating up and down a few notches. Anyone know what this means? I read somewhere it could be connected to the 12v, but nothing definitive.
     
  11. PriusCamper

    PriusCamper Senior Member

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    You're right on track with your plan... I always recommend first cleaning cooling fan and then replacing 12v to get all that out of the way before focusing on battery pack... Have you thought about what battery to buy yet?

    Myself and @Britprius who is wheelchair bound are big advocates of 55amp hour wheel chair batteries.

    Traditional cars use 12v batteries mostly to start the engine, aka: cold cranking amps.

    But in a Prius the hybrid battery starts the engine so instead of turning over an engine with 12v you're doing it with high voltage or ~220v.

    Because of this the 12v system is primarily running the computers and sensors so the most corrupt garbage battery builders like YellowTop Optima can get great reviews from misguided Prius owners and other 12v battery sellers can rip people off selling small-size batteries with high cold cranking amps in the near $300 range.

    So @Britprius and I tell people to save $100+ and head for the most commonly used computer back up power supply / wheelchair battery in the 55amp-hour range (20amp hours more than the ones the auto parts stores sell for way more money / cold cranking amps). For example a year ago I bought for a friend's Prius from BatteriesPlus for $140: Duracell Ultra 12V 55AH AGM SLA Battery

    These are the most common 12v batteries sold so they don't sit on a shelf growing old before you buy, they just grab 'em off the pallet from the latest delivery. The only challenge is the bolts that mount the terminals don't match up so you need to head to hardware store after buying the battery and purchase some longer bolts, as well as some correct size bushings, so the terminals mount to the battery properly.

    I installed one of these in my Prius in 2013 and though I get signs it's weakening, had I spent more money on something designed for non-hybrid cars I'd already be on my next battery by now.
     
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  12. Caleb2007

    Caleb2007 New Member

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    The battery you mentioned is $170 right now I believe. I can one at BatteriesPlus that I'm told is made for a 2007 Prius, it's got the Duracell name on it and it comes with a four year warranty. It's $215. If you have another example of the kind of battery you are talking about that is significantly cheaper and you believe to be just as good, let me know. I really appreciate your input.
     
  13. exstudent

    exstudent Senior Member

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    Direct fit, no terminal post modifications needed (JIS posts), 45AmpHr SKS, 12V AGM battery
    $146.24 Bosch, 4yr straight warranty, no proration
    $167.28 AC Delco, 2yr straight warranty, no proration
     
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  14. Caleb2007

    Caleb2007 New Member

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    I can't seem to find the 1st one you mention, the Bosh.
     
  15. Mendel Leisk

    Mendel Leisk Titanic Social Director

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    Pep Boys usually has the Bosch. Their website is a bit tricky tho, to enter vehicle type, find correct battery. But it's in there, somewhere. Or just phone them, let them do the checking.
     
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