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

Toyoto prius 2010 car battery draining

Discussion in 'Gen 3 Prius Technical Discussion' started by alexk345, Feb 20, 2024.

  1. alexk345

    alexk345 Junior Member

    Joined:
    Oct 22, 2022
    34
    0
    0
    Location:
    india
    Vehicle:
    2010 Prius
    Model:
    LE
    My car 2010 prius battery dies in 30 min after full charge. What is eating the charge so fast? I charged full last night and today morning it do not start. When i opened frontside i hear something is running I can go check battery strength but they will say battery is dead. 100%. Because they may want to sell the battery. My issue is this. even if i buy new battery if car is idle for 7 days .( i driver the car 20 mile every 7 days) , New battery also go down. So i am in dilemma

    • Discord | "2010 prius car battery issue" | The Car Community

    Anyone know how to check battery

    After fully charged with trickle down charger it shows 12.119v
     
  2. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,470
    8,383
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    You just have to buy a new battery, don’t over think it
     
    Brian1954 likes this.
  3. Brian1954

    Brian1954 Active Member

    Joined:
    Jan 31, 2021
    652
    246
    0
    Location:
    South Central PA, USA
    Vehicle:
    2011 Prius
    Model:
    III
    Here we go again with a new thread for the same issue that you have had with the 12v battery for many, many months. https://priuschat.com/index.php?threads/246683/

    Answer two questions:
    1. Did you buy a new 12v battery in the last two to three weeks?
    2. If not, then completely charge the 12v battery. With the car turned off, turn on the headlights for one minute and measure the voltage of the 12v battery with a volt meter. What was the voltage?
     
  4. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    8,043
    1,395
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    My friend the guy running the AutoZone battery tester or the one in advance Auto doesn't care about selling you a battery He really doesn't He doesn't get enough commission or anything like that He works in America in 2023 He gets nothing That's why these employees have bad attitudes don't really give a crap so on and so forth because well nobody else does either. So he doesn't really care about selling you a battery that little fancy machine that he brings out to measure your battery that thing is about $9,000 believe it or not or some insane price like that and they generally are pretty accurate they put a battery through its paces in 15 minutes or whatever it is and give you back a basic yay or nay type of condition thing. And generally that little machine is not incorrect and you're still having problems and so on and so forth but you don't want to believe it for whatever reason and that is your prerogative. What you do want to find is what's keeping the car draining the battery all the time as a way to hook your voltmeter up across the terminals and so on and see what kind of amps whatever is pulling The brake pump running every so often should not do this to a relatively decent battery the inverter cooling pump same thing the coolant heat storage tank system if your vehicle has this only comes on once after a 5-hour shut down for a few seconds so most of these things the car knows why it's turning them on quickly turning them off etc so unless your battery is just garbage these things shouldn't affect the 12 volt status so don't worry about having your battery checked that the big box store the big box store spends a lot of money on those battery checkers and they're pretty accurate You don't have to buy a battery right then because they're checking your battery but don't disbelieve what they're telling you because you don't want to buy a battery that's not good use of data.
     
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,683
    48,935
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    Unfortunately, you’ll have to go through every fuse to find the circuit that is draining the battery
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,647
    38,201
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Or if there is an abnormal drain. Around 20 milliamperes is normal, fwiw.

    That sounds like a battery in need of replacement.

    If practical, keep the new one on a good quality, smart charger, constantly between uses. If not practical, consider installing a battery disconnect device.
     
  7. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
    7,558
    4,431
    7
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    First you describe two different situations - does it drain in thirty minutes (easiest to diagnose) OR does it take overnight (requires more skill to test).

    1. Thirty minutes - either a huge amp draw larger than headlights on or a very bad battery.

    2. Overnight - a small amp draw like a hatch or map light or an obd2 adapter or aftermarket accessory or a weak battery.

    For number one, get a dc amp clamp meter (most are AC only) and measure the negative battery cable. Also take the battery in for a load test, best done with a full charge on it.

    For number two you need a series connected amp meter with the hatch latch manually closed with a screwdriver. It is two position - close the latch mechanism completely with the actual hatch open.

    Hook up like this and wait at least ten minutes. Amp draw should be 15-30 ma (thousands of amp).

    Prius v series ammeter parasitic draw setup.jpeg

    Either way, if you measure excessive parasitic draw, you then have to get more skilled. The best approach is to measure mv (thousands of a volt) across each fuse and fusible link. A fuse drawing current will have more mv.

    Another way is to pull fuses one at a time while monitoring ma in the back. Cautions include do one at a time and replace each before going to the next. Otherwise they will get mixed up.

    Another caution about pulling fuses is you restart ecu loads when replacing them in many cases. This causes a temporary increase in ma or amps as they start up and finally shutdown in sleep mode.

    Since it is 90% your battery and that is easiest, do that testing first.
     
  8. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,647
    38,201
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Took a crack at the step-by-step of the above:

    1. Connect jumper
    2. Disconnect battery neg cable from car body
    3. Connect ammeter between car body and battery neg cable
    4. Disconnect jumper
    5. Wait at least 10 minutes, then take readings. Start with manual scaling meter, start in amperage scale, then go down through milliamper scales.
    6. Reconnect jumper.
    7. Disconnect ammeter
    8. Reconnect battery neg cable to car body
    9. Disconnect jumper

    The jumper is employed to preserve the car's memories. If you don't care, it can be eliminated.
     
  9. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
    7,558
    4,431
    7
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    It also prevents ecu startup delays when initially measuring ma. In some meters the initial startup could exceed the meter’s fuse.
     
    Mendel Leisk likes this.
  10. alexk345

    alexk345 Junior Member

    Joined:
    Oct 22, 2022
    34
    0
    0
    Location:
    india
    Vehicle:
    2010 Prius
    Model:
    LE
    Today it went to 11.59v untouched and not connected to car

    Should i replace battery?
     
  11. alexk345

    alexk345 Junior Member

    Joined:
    Oct 22, 2022
    34
    0
    0
    Location:
    india
    Vehicle:
    2010 Prius
    Model:
    LE
    Battery after fulll charge with trickle charge when it say full
    12.119v
    Then next day
    measured - 11.59v

    Nothing connected
     
  12. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
    7,558
    4,431
    7
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    Voltage is low but is not definitive. A load tester and or age is recommended.

    Remember an old Prius battery will fool you into thinking 20% capacity is good because it starts.
     
  13. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,647
    38,201
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Yeah you seem to be thinking when your charger says "full" that your battery is good. A fully charged healthy battery would read close to or over 13 volts.

    I wouldn't even bother with a load test; that battery is toast.

    If you do want to load test, many automotive stores, in particular those selling batteries, have the modern load testers. For DIY, something like Solar BA9 is one example.
     
    bisco likes this.
  14. alexk345

    alexk345 Junior Member

    Joined:
    Oct 22, 2022
    34
    0
    0
    Location:
    india
    Vehicle:
    2010 Prius
    Model:
    LE
    Also i checked battery agm yellow top - 359 cad+ tax. amazon.ca
    Also if that do not work because of battery drain , i am doomed.

    I need a permanent solution.
    Locally no one selling prius battery in surrey bc
    canadian tire dont have battery for prius 2010

    Can someone list me rating for battery so i can find something similar to yellow top?
    May be someone sells used battery but higher voltage?
     
  15. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,647
    38,201
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Canadian Tire has had a battery compatible with 3rd gen Prius, maybe just not in stock right now. IIRC it was getting up around $260~280 CDN. < Yeah checked, nothing right now.

    What's the dealership asking these days? Last time I checked it was close to $400 CDN.

    Even you don't have excessive phantom draw, driving 20 miles once a week, you will continue to have dead batteries, until you start doing something, either keeping it on a charger constantly or disconnecting it between uses. That's just not enough use. Any modern car has a low but constant background need for electrons, to retain memories.

    You might try emailing SaskBattery. They had one when I checked a few months back, for low to mid $200's IIRC.
     
  16. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
    7,558
    4,431
    7
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    You need a S46B24R battery for a Prius. Often the dealer is the best value since their battery will typically last 8 years or longer.

    Don’t buy a Yellow Top, they are not great and don’t last nearly as long but still get a dealers price.

    The S46B24R battery is vented with a special port and the terminals are small. Trying to jam in the wrong battery can ‘doom’ you if it is installed with reversed polarity. It happens.

    In the US, Walmart and every auto supply has a S46B24R equivalent, usually less than $200 US.
     
    #16 rjparker, Feb 21, 2024
    Last edited: Feb 21, 2024
    Brian1954 likes this.
  17. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,647
    38,201
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Here's current link to saskbattery option:

    S46B24R (FP-AGM51JIS) - SaskBattery

    Last time I used them they ship cross Canada for free, and only charged GST. (poetic)

    Regarding how much driving is needed, my 2 cents: one or two stretches of protracted downtime your battery will be ok. But if you keep your battery on a steady diet of 20 miles once a week, it'll die pretty quick.
     
  18. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
    7,558
    4,431
    7
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    Nothing wrong with a battery maintainer for a garage queen. But a good battery takes care of you as does the car’s charging system which can do high rate charging when needed.

    IMG_4378.jpeg IMG_4376.jpeg
     
    #18 rjparker, Feb 21, 2024
    Last edited: Feb 21, 2024
  19. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,683
    48,935
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    if you can't plug in, disconnect the battery when not using
     
    Mendel Leisk likes this.
  20. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    8,043
    1,395
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    If they have a top line battery for a 2009 or 2008 that'll fit your 2010 I regularly move the batteries from the three to the two all the time and back and forth without any problem at all I'm using the I think it's the Sears Gold AGM