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

12v battery change and yellow brake light warning sign

Discussion in 'Gen 2 Prius Technical Discussion' started by daneferna, Nov 17, 2013.

  1. daneferna

    daneferna Junior Member

    Joined:
    Feb 25, 2012
    6
    0
    0
    Location:
    los angeles
    Vehicle:
    2007 Prius
    Model:
    N/A

    My husband just changed the 12v battery himself and now the yellow brake light warning signal is on the dash (!). He said he removed the 'supply assy brake control power' in order to install the 12v battery and when he reconnected it, the SABCP box made a spark when he put the last top screw in on (like a short circuit) when he attached it to the metal bracket that holds it in place. BTW, the car was on in the 'ready' position. Apparently, he had finished everything, turned the car on to make sure the 12v battery worked, saw a small screw he forgot for the SABCP box and then quickly screwed it in, then the spark.
    Soooooooooooo......What now? Is this a fuse that we can replace? Do we have to take it to the dealer? Is it safe to drive? Do we have to replace the SABCP box? is there anything we can do?!
    THANK YOU in advance !
     
    #1 daneferna, Nov 17, 2013
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,199
    6,464
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    The issue causing the spark is that the brake power supply unit is filled with electrolytic capacitors which charged up when the ground circuit was completed (via bolting the unit into place.) That surge of current caused the spark.

    Do a search for how to clear the skid control ECU DTC by using a jumper wire on the OBD-II socket. That may solve the problem.
     
    #2 Patrick Wong, Nov 17, 2013
  3. AzWxGuy

    AzWxGuy Weather Guy

    Joined:
    May 22, 2011
    968
    490
    0
    Location:
    Tucson, AZ
    Vehicle:
    2021 Prius
    Model:
    Limited
    I agree with what Patrick has said above, but maybe there has been some damage to the SABCP. Thinking about the battery replacement procedure, the short 10mm bolt that attaches to the top of the SABCP could be confused with another longer 10mm bolt used elsewhere (either a hold-down bolt on the HV battery ventilation exhaust pipe or the inboard 12V battery mounting bracket, can't remember which). I also don't know how close any components inside the SABCP might be to where a longer bolt might break through the case and short them out. I always make it a point to have everything bolted back in place and connected back up before reconnecting the negative clip on the battery.
     
    #3 AzWxGuy, Nov 17, 2013
  4. daneferna

    daneferna Junior Member

    Joined:
    Feb 25, 2012
    6
    0
    0
    Location:
    los angeles
    Vehicle:
    2007 Prius
    Model:
    N/A
    Thanks for the advice. I am going to do that search and try it in the morning and let you know how it went. I will also talk to my husband about the lengths of the bolts and the correct placement of them. Btw, forgot to mention it is 2007 prius just in case that is relevant. Thanks again!
     
    #4 daneferna, Nov 18, 2013
  5. daneferna

    daneferna Junior Member

    Joined:
    Feb 25, 2012
    6
    0
    0
    Location:
    los angeles
    Vehicle:
    2007 Prius
    Model:
    N/A
    Yes, my husband said that he did confuse the short and long bolt, but put them back in the correct place (obviously after the spark). So do that mean the SABCP could be permanently damaged?
     
    #5 daneferna, Nov 18, 2013
  6. daneferna

    daneferna Junior Member

    Joined:
    Feb 25, 2012
    6
    0
    0
    Location:
    los angeles
    Vehicle:
    2007 Prius
    Model:
    N/A
    Patrick, we just did the skid control ECU DTC with jumper wire, and the yellow (!) light was steady, but now that ABS light is flashing (which is new) and there is no code, or perhaps I don't know how to read it. I will look into that. And we were unable to reset the light brake control light (!) after putting jumper wire in 4 and 13 when ig-off, and then making it ready and pumping brake 8x in 5 seconds then taking jumper wire out while still in ready. We removed the jumper wire and the ABS light was flashing, and then after turning car off and on the ABS light is now off, but the yellow (!) light is still on. Thank you! (also, did you see my post above that my husband did accidentally switch the screws which may have caused spark).
     
    #6 daneferna, Nov 18, 2013
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,199
    6,464
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    At this point, I suggest that you seek professional assistance either at a Toyota dealership or an independent who specializes in Toyota hybrids. It might be necessary to replace the brake power supply (you might be able to obtain a used unit at a salvage yard); or perhaps the car has another problem.
     
    #7 Patrick Wong, Nov 18, 2013
  8. daneferna

    daneferna Junior Member

    Joined:
    Feb 25, 2012
    6
    0
    0
    Location:
    los angeles
    Vehicle:
    2007 Prius
    Model:
    N/A
    Thanks Patrick for the help. Quick question, could it be possible we switched the 4 and 13 slots?
     
    #8 daneferna, Nov 18, 2013
  9. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,199
    6,464
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    When you look at the OBD-II socket, you'll notice that it has a trapezoid shape, with one base wider than the other. The numbering starts with 1 at the far right of the wide base and ends up at 8 at the far left of the wide base. Then the numbering continues with 9 on the far right of the narrow base and goes to 16 at the far left of the narrow base.

    Once you have the jumper installed between pins 4 and 13 and the Prius is READY, see what two digit blink code comes back from each of the three brake warning lights: ((!)), ABS, and VSC. If you can retrieve the code maybe we can suggest what is wrong.
     
    #9 Patrick Wong, Nov 18, 2013
  10. daneferna

    daneferna Junior Member

    Joined:
    Feb 25, 2012
    6
    0
    0
    Location:
    los angeles
    Vehicle:
    2007 Prius
    Model:
    N/A
    Thank you again for your time and the quick and consistent replies. I will try again tomorrow.
     
    #10 daneferna, Nov 18, 2013
  11. AzWxGuy

    AzWxGuy Weather Guy

    Joined:
    May 22, 2011
    968
    490
    0
    Location:
    Tucson, AZ
    Vehicle:
    2021 Prius
    Model:
    Limited
    Once again I will have to agree with Patrick and suggest you seek professional assistance.
     
    #11 AzWxGuy, Nov 19, 2013
  12. jdenenberg

    jdenenberg EE Professor

    Joined:
    Nov 21, 2005
    3,837
    1,828
    1
    Location:
    Trumbull, CT
    Vehicle:
    2020 Prius
    Model:
    LE AWD-e
    There is a qualified, independent repair facility in southern CA. see: Avi's Advanced Auto Homepage. Avi can help you.
     
    #12 jdenenberg, Nov 19, 2013
    daneferna likes this.
(You must log in or sign up to post here.)