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

CTEK Polar hookup for Prius c

Discussion in 'Prius c Main Forum' started by StirFly, Feb 11, 2024.

  1. StirFly

    StirFly New Member

    Joined:
    Feb 11, 2024
    13
    2
    0
    Location:
    Boston area
    Vehicle:
    2014 Prius c
    Model:
    N/A
    New guy here, 2014 Prius C that's had the starting battery replaced several times, last time w an OEM one, less than a year ago, still needs a jump a lot because we don't drive much. (Got a Clore JNC770R, makes the car usable!) Sick of that, and want it to be easier for my wife when I'm out of town, so I just bought the CTEK (56-958) MUS 4.3 POLAR, which so far seems to be working great.

    But, I'd like to make connecting and disconnecting it easier, again a lot for my wife when I'm not around, something she can just plug in instead of messing around under the hood, opening the power box, etc. However, the ring connectors on the "Comfort Indicator Eyelet" (wacky name) are too small to fit the Prius C's battery posts, and I'm trying to figure out an alternative.

    I haven't so far found similar size ring connectors with a lug opening that big (10mm or 7/16" I'm guessing), except some huge copper ones from NAPA (NW 785911) that are built for much larger wire, max wire size 2/0 ga. I can cut off the original ones and solder the wires to these, but they're MUCH smaller, so there won't be any strain relief at all.

    I've emailed CTEK about this, haven't heard back, yet, hopefully, but who knows how responsive they'll be.

    Any great ideas?

    Thanks.
     
    bisco likes this.
  2. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,488
    3,763
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    I have my CTEK pigtail (without the "comfort battery indicator part" attached directly to the positive and negative posts of my battery. I removed the 10 mm-head bolt on each terminal clamp and sandwiched it between the bolt head and the clamp and I have no recollection of having size issues in doing that. I also have a Gen 2 so YMMV, unless someone did a JIS pencil post to US SAE conversion of the clamps on your C.
     
  3. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,674
    38,219
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    For mine (Gen 3) I connect positive where the main positive wire (thick/white) goes into the under hood fuse box, and for negative I found a nearby unused threaded hole near the fender; secured it there with a scrounged metric bolt. Any existing bolt attaching directly to the body would be a good option.
     
  4. StirFly

    StirFly New Member

    Joined:
    Feb 11, 2024
    13
    2
    0
    Location:
    Boston area
    Vehicle:
    2014 Prius c
    Model:
    N/A
    Maybe this should have been obvious, but the CTEK pigtail ring connectors aren't supposed to go around the battery posts themselves, just around the bolts that attach the existing wires to the posts. Got mine hooked up that way today.

    Two beefs:
    - The metal of the ring connectors on the pigtail is really cheap and thin, wouldn't surprise me if they're fragile.
    - The ergonomics of connecting and disconnecting are different than popping the hood, fuse box and connector cover open and clipping in there but it's not wildly more convenient.
    a) There isn't a really great place to put the pigtail so it's out of harms way but accessible.
    b) You have to crack a window to run the cable to the inside of the car.

    Nothing fatal, just not great to use, but it seems to be keeping the battery happy so far.
     
    #4 StirFly, Feb 17, 2024
    Last edited: Feb 17, 2024
  5. StirFly

    StirFly New Member

    Joined:
    Feb 11, 2024
    13
    2
    0
    Location:
    Boston area
    Vehicle:
    2014 Prius c
    Model:
    N/A
    Mendel, can you explain a bit more how you make the positive connection? I think I know the thick white wire you mean inside the fuse box, but I don't see a good way to connect the CTEK to it.
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,674
    38,219
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    On our Gen 3’s under hood fuse box the heavy gauge, white (positive) wire has a ring connector, under a black plastic sheath that is somewhat tricky to remove. A small bolt secures that ring connector. I removed that bolt, and added the CTEK’s similar ring connector, reinstalled bolt. The CTEK’s ring connector had a plastic shoulder that prevented it from being bent sufficiently to allow the plastic sheath to go back into place; I needed to trim that shoulder back near-completely.

    video #23 here shows how to remove that sheath, on Gen 3 Prius. Not sure how similar the Prius c is.
     
    #6 Mendel Leisk, Feb 18, 2024
    Last edited: Feb 18, 2024
  7. StirFly

    StirFly New Member

    Joined:
    Feb 11, 2024
    13
    2
    0
    Location:
    Boston area
    Vehicle:
    2014 Prius c
    Model:
    N/A
    This is what the fuse box looks like in my 2014 Prius c. White wire is pretty obvious, but I don't see a ring connector on either end.
     

    Attached Files:

  8. StirFly

    StirFly New Member

    Joined:
    Feb 11, 2024
    13
    2
    0
    Location:
    Boston area
    Vehicle:
    2014 Prius c
    Model:
    N/A
    Whatched the video, I see.

    Not sure if my wife would be happier opening the hood and connecting to the pigtail there, or dealing with the pigtail being somewhat in the way in the back seat.
     
  9. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,674
    38,219
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Ok, good. And yeah, think I partially led you astray with a flakey memory, the "white wire". Here's where it is on our 3rd gen, under that plastic cover.

    I was up in the air too, regarding where to install the quick connect. I was thinking to run it out the front grill, but anything readily accessible from outside could be subject to vandalism; someone could short out your battery. I did the quick connect under the hood, right at the fuse box, and to connect I pop the hood and raise, connect to the charger, then lower the hood to the ajar position, not fully closed. We're garage stored though.
     

    Attached Files:

    #9 Mendel Leisk, Feb 18, 2024
    Last edited: Feb 18, 2024
  10. StirFly

    StirFly New Member

    Joined:
    Feb 11, 2024
    13
    2
    0
    Location:
    Boston area
    Vehicle:
    2014 Prius c
    Model:
    N/A
    The posted video about removing the battery shows a clear plastic protector over the whole battery, and protective caps over the terminals.

    My 2014 Prius c has neither of those. The battery was already replaced, by a local shop I more or less trust. I doubt they just got rid of those without asking or saying anything, and the car wasn't new when it came to me.

    Are those pieces necessary or advisable?
     
  11. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,703
    48,947
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    what posted video?
     
  12. StirFly

    StirFly New Member

    Joined:
    Feb 11, 2024
    13
    2
    0
    Location:
    Boston area
    Vehicle:
    2014 Prius c
    Model:
    N/A


    But I remembered wrong about caps over the terminals.
    There is a plastic cover over the whole battery, which I've never seen on mine, but I didn't get it new, and the battery has been replaced (with one from Toyota) while I've owned it.

    I doubt that cover matters, which is what I'm asking.
    Does it?
     
    bisco likes this.
  13. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,703
    48,947
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    The plastic cover is interesting, I’ve never seen it mentioned. No idea what it’s for, except to protect the seat bottom?
    I’d bring the video to a dealer part’s department and ask if they sell it.
    You could make something out of a plastic bag.