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Installing a battery maintainer on 12 v Prius C battery

Discussion in 'Gen 4 Prius Technical Discussion' started by MICHAEL RUBY, Apr 26, 2022.

  1. MICHAEL RUBY

    MICHAEL RUBY Junior Member

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    Jul 28, 2020
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    Location:
    Seattle WA
    Vehicle:
    2018 Prius c
    Model:
    III
    I've been having problems with the 12 volt battery going to zero on me because I don't drive it on long enough trips to keep it charged up. The AAA battery guy is getting tired of me so he says I should install a battery maintainer on the 12 volt. It seems you need to do this at the battery under the seat and not at the special connection under the hood. But using clips is not really an option in the close space if you want to close it up again and leave the connection in place so you don't have to take the seat apart the next time. The battery maintainer I looked at has some screw on optional connectors but I can't figure out where you would attach them. The Toyota dealer service guy said they could install it but would charge me $150. Can anyone give me some advice about the right way to do this? Oh, also there are 0.8 amp and 1.0 amp maintainers. Any advice about which to buy?
     
  2. bisco

    bisco cookie crumbler

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    boston
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    Plug-in Base
    no problem attaching it under the hood, many do it with good results. you're fortunate, toyota forgot to put a jump point in the early c's.

    this is the gen 4 forum btw
     
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  3. FuelMiser

    FuelMiser Senior Member

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    Vehicle:
    2016 Prius
    Model:
    Touring
    Typically, you would attach them on the bolts that secure the battery cables to the battery posts. You would remove the nut from the bolt that secures the cable, insert the eyelet from the charger connection and re-attach the nut. Then you route the pigtail to some location outside the battery compartment so it is accessible to the charger.
     
  4. FuelMiser

    FuelMiser Senior Member

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    Touring
    Some pics to illustrate my post above. NOTE: this is not a Prius battery

    tempImage8DTjed.png tempImageJw8pas.png tempImageajwCM0.png