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  1. Bob Holliston

    Bob Holliston Junior Member

    Joined:
    Jun 12, 2012
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    Vehicle:
    2005 Prius
    Model:
    N/A
    My 2005 Prius (86 K mi.) has a warning light on - brakes. Put on the scanner and came up with code P1116 coolant temp. sensor circuit stack for coolant heat storage system. Also C1378 - capacitor communication circuit malfunction. Any ideas? I'm just a shade tree mechanic but can usually fix stuff if I know where to start. I'm allergic to dealerships. Thanks, Bob
     
  2. dorunron

    dorunron Senior Member

    Joined:
    Jul 17, 2011
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    Location:
    Houston, TX
    Vehicle:
    2013 Prius
    Model:
    Three
    Doing a google search revealed this string here on PC.

    2007 Prius P1116 code and coolant control valve issues | PriusChat

    Sorry I can't help you anymore than that.

    Ron
     
  3. nh7o

    nh7o Off grid since 1980

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    Location:
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    Vehicle:
    2009 Prius
    Model:
    II
    The C1378 is concerned with the auxiliary 12V power supply, located in the rear of the car near the 12V battery. It says that the communication from the aux. power supply and the skid control ECU (which is in the front of the car) is not correct. The trouble areas are the harness wires, the 12V aux supply, or the Skid ECU itself.

    Look for evidence of rodent chewing on the wires. Otherwise, you might have to continuity test the harness wires to make sure. If they are OK, then you might have to try replacement of the skid ECU with a used unit. I have yet to hear of a 12V aux power supply going bad here on PC, but that is a possibility.
     
  4. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    Apr 14, 2009
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    Location:
    Greenwood MS USA
    Vehicle:
    2012 Prius v wagon
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    Three
    Merkey likes this.
  5. Bob Holliston

    Bob Holliston Junior Member

    Joined:
    Jun 12, 2012
    31
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    Vehicle:
    2005 Prius
    Model:
    N/A
    Thanks guys. This car was rearended and after repair I reinstalled the battery and didn't plug in that little connector. I bought it wrecked and ASSumed the lite was on when I bought it. Thanks again, Bob
     
  6. TWOPrius

    TWOPrius Junior Member

    Joined:
    Feb 15, 2012
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    Location:
    Tampa
    Vehicle:
    2011 Prius
    Model:
    III
    I just discovered this code, plus C1371, C1256. No CEL, but accumulator runs often. Will check aux battery. Its a yellowtop less than a year. But connections can deteriorate wouldn't know where to begin the check for accumulator leak

    Posted via the PriusChat mobile app.
     
  7. TWOPrius

    TWOPrius Junior Member

    Joined:
    Feb 15, 2012
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    Location:
    Tampa
    Vehicle:
    2011 Prius
    Model:
    III