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

Gaining access to HV battery area

Discussion in 'Gen 2 Prius Accessories & Modifications' started by brewer, Nov 1, 2005.

  1. brewer

    brewer New Member

    Joined:
    Nov 1, 2005
    1
    0
    0
    I have a DC clamp meter that I want to measure the battery current while in stealth mode and regen braking mode
    by clamping over the main battery cable

    I was told by the local dealer (Sydney, Australia) that opening the battery compartment would trip some hidden microswitch and shutdown the computer

    Not sure if its true or just intimidation by Toyota

    The battery seems well secured & removing some of the access bolts didnt get me anywhere
    Anyone have a method I can use to get access to the cable ?
    thanks
    M
     
    #1 brewer, Nov 1, 2005
  2. Lather

    Lather New Member

    Joined:
    Sep 25, 2005
    27
    0
    0
    #2 Lather, Nov 1, 2005
  3. efusco

    efusco Moderator Emeritus
    Staff Member

    Joined:
    Nov 26, 2003
    19,891
    1,192
    9
    Location:
    Nixa, MO
    Vehicle:
    2004 Prius
    Model:
    N/A
    I don't have/can't give you exact details, but see the link below (scroll down a bit from the picture that opens up) and see if that doesn't give you some clues.

    PLEASE be very careful. You can trip some kind of breaker in there, IIRC, but you should be able to reset it.

    http://privatenrg.com/#2004Ah%20work
     
    #3 efusco, Nov 1, 2005
  4. Lather

    Lather New Member

    Joined:
    Sep 25, 2005
    27
    0
    0
    Nice site, thanks. I got some reading to do.

    So that's where the current sensor is. I've already got the back stripped down and the battery box exposed (I threw a few pieces of dynamat on it so I wouldn't have to hear the clicking).

    So, if I had the 12V system disconnected anyway (amp install) and I opened it up, do you think it run afterwards w/o problems.?
     
    #4 Lather, Nov 1, 2005
  5. efusco

    efusco Moderator Emeritus
    Staff Member

    Joined:
    Nov 26, 2003
    19,891
    1,192
    9
    Location:
    Nixa, MO
    Vehicle:
    2004 Prius
    Model:
    N/A
    Sorry, I'm not sure what you're asking. Are you asking if you open the HV battery case would it run afterward OK? I think so. Again, I think there is some fuse or breaker in there that can trip if you touch the wrong thing. And you might generate a MIL code and have some lights on the dash for a few starts, but unless you do something really dumb I doubt you'd have any serious problems.

    Disclaimer: The link above is NOT my site. I've never opened the HV battery case and probably never will by myself. The stuff I'm telling you is what I remember hearing from others who have and don't vouch for the accuracy one little bit. The HV battery CAN KILL YOU so please don't screw with it unless you're sure you know what you're doing, have reviewed the wiring diagrams (and know how to interpret them) and the appropriate sections in the repair manual. This is serious business.
     
    #5 efusco, Nov 1, 2005
  6. Frank Hudon

    Frank Hudon Senior Member

    Joined:
    Jan 11, 2004
    4,147
    18
    0
    probably the best way, as I assume you want to watch the clamp-on while some one drives the car, is to remove the back seats top and bottom and where the 2 cables exit the car just in front of the shock tower, put your clamp-on on the wire there. Positive or negative who cares if you clamp-on reads +-DC as when you start off it'll give negative readings anyhow so if positive readings occure your going to have to clamp the other wire. If your clamp-on is A/C only your out of luck as the feed to and from the battery is DC, it's converted at the inverter end and not the battery end of the system.
     
    #6 Frank Hudon, Nov 1, 2005
  7. tomdeimos

    tomdeimos New Member

    Joined:
    Feb 16, 2004
    995
    2
    0
    Location:
    Lexington, MA
    Evan,

    Nice pictures on that web site! And hope you noticed one engine shot shows the block heater hole we can't see and everyone has trouble finding!
     
    #7 tomdeimos, Nov 1, 2005
  8. Lather

    Lather New Member

    Joined:
    Sep 25, 2005
    27
    0
    0
    If it triggers a sensor meant for the computer, hopefully I'm okay since the battery would already be disconnected. If it does something to the 200V side, I'm probably screwed.

    But that other site looked interesting. I've been interested in measuring current on both the 12V and 200V side as well a a tachometer. If there's a better way, I'd go for it.
     
    #8 Lather, Nov 1, 2005
  9. Frank Hudon

    Frank Hudon Senior Member

    Joined:
    Jan 11, 2004
    4,147
    18
    0
    is there a better way? yes there is it's called the CAN-VIEW monitor and here's the link
    http://www.hybridinterfaces.ca/
    all the info your looking for and more.
     
    #9 Frank Hudon, Nov 1, 2005
  10. hdrygas

    hdrygas New Member

    Joined:
    May 22, 2004
    3,650
    6
    0
    Location:
    Olympia Wa
    Vehicle:
    2004 Prius
    Oooh I have one of those I never thought about using it! I think my seats are about to come up! One more data point. Some one needs to get a Minni Scanner to me or I will have 25 or 30 meters in the car and the weight of all that instrumentation will kill my milage. Do you suppose there is a 12 step program?
     
    #10 hdrygas, Nov 1, 2005
  11. hobbit

    hobbit Senior Member

    Joined:
    Mar 23, 2005
    4,089
    468
    0
    Location:
    Bahstahn
    Vehicle:
    2004 Prius
    Model:
    N/A
    F'krissake. Go whack that dealer upside the head, he's LYING
    through his teeth. There is no such "microswitch".
    .
    See http://techno-fandom.org/~hobbit/cars/imeter/ for much poop
    about the battery box and reading the current sensor and why working
    around the battery is really not much different from working on
    household electrical stuff -- except that DC tends to burn rather
    than tingle.
    .
    _H*
     
    #11 hobbit, Nov 12, 2005
(You must log in or sign up to post here.)