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2005 Prius (!) Code 1377 inf 109 indicating open circuit at brake control power supply

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Cimorene, Jan 6, 2020.

  1. Cimorene

    Cimorene Junior Member

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    2005 Prius
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    Plug-in Base
    I have the repair manual which I did read over. Im very close to solving this so I'm hoping for some help over the finish line. I like many others replaced my 12v battery. Nothing out of the ordinary, but immediately after I did get the yellow brake indicator. I mayve snagged one of the wires that go into the top of the battery when I removed it. I did visually inspect my fuses, but I dont have a multimeter (I ordered one, it'll be here tomorrow).

    1377 with 109 says this Open circuit between auxiliary battery (12 V) and brake control power supply power input (+BC terminal).

    With the location below

    Harness and connector
    ABS No.3 fuse

    However, I do think I snagged one of the wires when removing the brake power supply. After looking at the repair manual it doesnt really tell me what to do. It looks like "repair or replace harness or connector". I honestly don't know what a harness or a connector is. Is it the 3 wire groups that go above the battery and the one that goes into the brake power supply? Thanks for your help in advance. I tried my best, but Im just stuck on this last little part
     
    SFO likes this.
  2. JC91006

    JC91006 Senior Member

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    It's probably the connector/wires that go into the brake power supply. Visually inspect the wires and see if any of them have been yanked out (in the connector that connects to the brake power supply)
     
  3. Cimorene

    Cimorene Junior Member

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    2005 Prius
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    Plug-in Base
    I did remove them and inspect them. I plugged then back in. They look fine. The one with only 1 wire seems a little flimsy, but other than that I cant see a problem. I looked at them, they look good. I did that earlier today. The one wire I believe connects to the battery and not not into the actual brake control. If thats the problem what do I do?
     
  4. Cimorene

    Cimorene Junior Member

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    2005 Prius
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    Plug-in Base
    Oh i didnt realize that they are part of the entire wiring harness. I thought they were stand alone in a way. I saw some diagrams and that makes sense. The lead sensor appears to be the one that looks a little iffy. The other two appear fine although Im not entirely sure what Im looking at.

    Here is a picture. The 3 are the sense lead, brake power, and main + lead

    <Apparently Im not allowed to post links yet, but I found a photo of the 3 cords that are part of the battery and brake power box.


    I can't imagine its the main + lead since I would think the 12v wouldnt work. The sense lead might be an issue, but it does go in just fine. The other brake power one is heavy duty and definitely requires a push, but then clasps in
     
  5. Cimorene

    Cimorene Junior Member

    Joined:
    Dec 8, 2019
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    Location:
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    Vehicle:
    2005 Prius
    Model:
    Plug-in Base
    By the way, this morning I just went ahead and picked up fuses for ABS 3 and the light came off without having to reset. I hope it stays that way! Sometimes you need to just try the easiest thing instead of getting worried about it (like me).
     
    bisco likes this.