12V battery dying every winter

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by SweKiwi, Dec 1, 2019.

Tags:
  1. SweKiwi

    SweKiwi Junior Member

    Joined:
    Jan 1, 2018
    16
    8
    0
    Location:
    Sweden
    Vehicle:
    2008 Prius
    Model:
    N/A
    Hi everyone!

    I have a Prius -07/-08 that keeps dying on my almost every winter.
    I've had the battery changed 3 times and I'm starting to wonder if it is normal when you drive as little as we do.

    We take the car to supermarket to get groceries 1 time/week.
    The distance is about 14 km back and forth.

    Are there any other Prius 2nd generation owners here, that have experienced the same problem?

    ... also where is the best place (do you find) to place the negative (black) jumper cable to?
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    40,879
    29,349
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    The car is constantly making a low-level demand on the 12 volt battery. Regular, near-daily driving will keep it charged. But regularly sitting idle for up to a week, the battery will not charge enough.

    Our situation is similar, albeit not quite as extreme. I use a CTEK 4.3 external battery charger regularly. On any day the car is not being used I will connect it and let it do a full charge regimen (this might take 3~6 hours), then just leave it connected till the car is next used.

    My charger came with an extra connector cable for permanent attachment to the car, which I used: it makes for a more secure and convenient connection points. I've connected it where the 12 volt positive cable feeds into the under-the-hood fuse box. Other than that it also has alligator style clips, which can be connected at the jump-start point, also in the under-the-hood fuse box

    Left connect like this, it just continues to monitor the battery, and does very low level "maintenance" charging.

    For charging like this it is best if you're in an enclosed garage, with access to regular alternating current electricity. Different countries with different voltages, you need to research chargers suitable for your area. You want a "smart" charger, one that assesses the battery, runs a multi-stage charging regimen, then settles down to "maintenance" charging, that can be left on indefinitely. Most will have optional charging methods; read up carefully as to which is most appropriate.

    Also, for 2nd generation Prius like yours, the Owner's Manual (North American at least), recommends max. charging rate of 3.5 amperes. In North America the CTEK 3.3 is in that range (I have one of those too, works good), and the 4.3 (my current used one) might be a bit too high. It also cautions "if charging the battery in the vehicle be sure to disconnect the ground cable". I've never followed that advice, no problems.

    Oh, I just googled "what country manufactures CTEK chargers", and I think you're in luck. :)

    I'm just going to go out and connect ours now.

    IMG_1577.JPG
    IMG_1578.JPG IMG_1579.JPG
     
    #2 Mendel Leisk, Dec 1, 2019
    Last edited: Dec 1, 2019
    Georgina Rudkus, bisco and SweKiwi like this.
  3. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    40,879
    29,349
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    This might be good:

    MXS 3.8

    I'm struggling with the language, but guessing it's 3.8 amperes, which is not much above the 3.5 specified in Owner's Manual.

    Also, that link "acts up" if I click it, maybe something to do with cookies. It's this:

    upload_2019-12-1_7-45-4.png
     
    #3 Mendel Leisk, Dec 1, 2019
    Last edited: Dec 1, 2019
    SweKiwi likes this.
  4. sam spade 2

    sam spade 2 Senior Member

    Joined:
    Mar 31, 2018
    4,104
    1,778
    0
    Location:
    USA
    Vehicle:
    2017 Prius c
    Model:
    Four
    Yes. You NEED a battery tender.
     
    SweKiwi likes this.
  5. SweKiwi

    SweKiwi Junior Member

    Joined:
    Jan 1, 2018
    16
    8
    0
    Location:
    Sweden
    Vehicle:
    2008 Prius
    Model:
    N/A
    Thank you both!
    Especially you Mendel Leisk for taking so much of your time to both write and take pictures
    Unfortunately we do not have a garage.

    A mechanic as ordered some kind of device that connects to the port we have in the front of the car, where you plug in a cable for electricity to the engine-heater and the interior-heater. It will also charge the battery when hooked up to electricity.

    At home we have an electric connector (like a pole) that grants us 30 minutes every time you hold a button on this pole. This is not optimal, but at least once (1) every week I am taking the car to work (to go grocery shopping) and there it hangs on charging for at least 8 hours whilst I'm working.

    I did this once every 4 weeks with a DEFA SmartCharger and it worked perfect last winter from januari to april. After that I did not charge the car once during the spring and summer... until it died 2 weeks ago.

    The DEFA smart charger: SmartCharge 4A • DEFA Testvinnande batteriladdare för bil och båt

    But I guess the built-in-charger we are getting installed will solve this very, very frustrating issue #strandedwithaflatbattery I assume?
     
    Raytheeagle, bisco and Mendel Leisk like this.
  6. SweKiwi

    SweKiwi Junior Member

    Joined:
    Jan 1, 2018
    16
    8
    0
    Location:
    Sweden
    Vehicle:
    2008 Prius
    Model:
    N/A
    Have you also had this problem with your 12V battery?
     
  7. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    40,879
    29,349
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Yes. The engineers designing the car assume consider it being used almost daily, and not just short trips. For what's worth 14 kms is not a bad length of trip. But as infrequently as once a week, is not good. There is a constant background drain of approx 20 milliamperes, for the car to maintain memories, be ready to detect the "key" when you approach, and so on.

    Our battery is on the charger more than off, and in great shape, over 4 years old. I check with Solar BA5 (electronic load tester) occasionally. Now Solar BA9 is more readily available, and there are many similar testers. Or even just a digital multimeter will give you fairly good idea how it is. Check first thing in morning, with the car off, at the under the hood jump point.

    But I'm sure if I didn't have it constantly connected it would be a different story. We drive the car maybe every 3rd day, on average. Sometimes several days in a row, then not for 4 or even more days. And often it's only 4~5 kms drive.
     
  8. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    90,023
    40,383
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    if you have sks system there should be an off button under the steering wheel which reduces battery drain
     
    dig4dirt and Mendel Leisk like this.
  9. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    40,879
    29,349
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Yeah, from North American 2nd generation Owner's Manual (page 33):

    upload_2019-12-1_10-32-42.png
     
    dig4dirt likes this.
  10. sam spade 2

    sam spade 2 Senior Member

    Joined:
    Mar 31, 2018
    4,104
    1,778
    0
    Location:
    USA
    Vehicle:
    2017 Prius c
    Model:
    Four
    No but thousands of others HAVE.....and the make or model of car really makes little difference.
    The battery slowly loses it's charge when not in use.......and when not fully charged wears out quicker.

    There really is no need to buy additional hardware.......except the heaters might be good where you live.
    The procedure you used successfully before is fine for the battery itself.

    At some point, you probably should check the voltage of the charging system when the car is running but I don't remember many or any reports of that failing.
     
  11. SweKiwi

    SweKiwi Junior Member

    Joined:
    Jan 1, 2018
    16
    8
    0
    Location:
    Sweden
    Vehicle:
    2008 Prius
    Model:
    N/A
    Thanks for the well-explained answer and also the image of whereas it is shown where this button is. I might just try this button if we get a dead battery once again.

    I am so relieved that it is how the car is made and not that we might have a battery-leakage (except for the "normal" one that you are describing). We just had the charger installed under the hood, I'll send some pictures just to show what the mechanic did.

    One issue (I hope won't be an issue) is that we only can draw electricity from our home parking in about 30 minutes at a time. There is not constant electricity. But. Would you guys say it would suffice with charging it at 8 hours at work when I go grocery shopping? Could that be enough to keep the battery strong?

    ... when i think about it, I only charged the battery once a month during last winter for about 8 hours (at work).

    I guess it will be a trial and error thing (as long as keep killing the battery doesn't wear it down to uselessness...)

    A last question: What voltage should the "Voltmeter " show when I check it? I've hade few different answers and should I always check it when the car has been turned off (like in the morning, before using it)?

    This is what it looked like last year:

    [​IMG]


    Thank you for your answer as well. But my problem with the battery suggests that I need some additional hardware if you are using as seldom as we are and having these harsh weather conditions with lots of snow and cold.

    ... again - thank you both so much for your elaborate answers!
     
    Mendel Leisk likes this.
  12. sam spade 2

    sam spade 2 Senior Member

    Joined:
    Mar 31, 2018
    4,104
    1,778
    0
    Location:
    USA
    Vehicle:
    2017 Prius c
    Model:
    Four
    Your original post led me to believe that you already had a battery tender-type charger.
    And that is all you really need to keep the battery charged.

    Of course, that won't help take the chill off the engine.......but that is a different problem.

    The trick here is to keep the charger active as much as possible on the days when the vehicle is NOT used.
    30 minutes once or twice per day when not used should be enough to accomplish that.......IF the battery is healthy AND there aren't any other hidden problems.

    But I just had a thought: IF you have to move the car TO the outlet to charge and then move it away again after a half hour.......that situation might negate the short charge you are able to put into it.
     
    SweKiwi likes this.
  13. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    40,879
    29,349
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    That intermitant power could be troublesome. Not sure.
     
  14. sam spade 2

    sam spade 2 Senior Member

    Joined:
    Mar 31, 2018
    4,104
    1,778
    0
    Location:
    USA
    Vehicle:
    2017 Prius c
    Model:
    Four
    IF......you can connect and disconnect the power without starting the car......then there is nothing "troublesome" about it, not for the car or battery anyway.

    Some battery tenders completely remove the charging and then monitor the voltage to know when/if the charging needs to be re-applied.
    Same thing as connecting the leads yourself.
     
  15. SweKiwi

    SweKiwi Junior Member

    Joined:
    Jan 1, 2018
    16
    8
    0
    Location:
    Sweden
    Vehicle:
    2008 Prius
    Model:
    N/A
    Thanks for all your interesting answers!

    I am not moving the car to and from the charging station. There is a "pole" at my parking space which I connect the cable to the front and then it just sits connected until the day I leave.

    It might be that the battery is not as healthy as before (since it have died twice). But. Thus far it hasn't died on me since getting the charger. My most important lesson is that the battery would never have survived with how seldom and short distances we use it.
    ... for that, I am very grateful.
    ... especially when we might have this fix that did not cost us more than $230 with the installation and the equipment.

    Thanks guys
     
    Mendel Leisk likes this.
  16. sam spade 2

    sam spade 2 Senior Member

    Joined:
    Mar 31, 2018
    4,104
    1,778
    0
    Location:
    USA
    Vehicle:
    2017 Prius c
    Model:
    Four
    BUT.....in an earlier post, you indicted that there is a timer on the electrical outlet, only supplying power 30 minutes at a time.
    If that still is the case, you are going to need to "push the button" two or three times a day or else your nice new equipment will do NOTHING for you.
     
  17. Georgina Rudkus

    Georgina Rudkus Senior Member

    Joined:
    Sep 15, 2018
    1,092
    901
    0
    Location:
    Taylors, SC
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    I do the same thing, but mine is connected directly to the 12 volt battery in the rear.
     
    Mendel Leisk likes this.
  18. SweKiwi

    SweKiwi Junior Member

    Joined:
    Jan 1, 2018
    16
    8
    0
    Location:
    Sweden
    Vehicle:
    2008 Prius
    Model:
    N/A
    So far the car has been running. It has not been that cold yet (mostly rain and about +3 Celsius). Also I'm only charging it perhaps 30-60 minutes every day/morning (when the timer on the pole activates).

    Thanks again for the information! It has been huge relief :)
     
    bisco and Mendel Leisk like this.
  19. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    90,023
    40,383
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    keeping it topped up for 30-60 minutes a day is fine. it's the week long drainage that causes issues.
     
Loading...