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2006 Prius with error codes C1241 and C1378

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by callibeth, Jul 18, 2011.

  1. callibeth

    callibeth New Member

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    Took my car into the dealer because the ! came on in connection with brakes. They pulled error codes C1241 and C1378, and say the answer is $1,750 for a new skid control ECU.

    C1241 indicates a problem with the Ig2 power source circuit.
    C1378 indicates a problem with brake control power supply, the skid control ECU, or the wiring harness.

    This car has had numerous electrical problems. Battery had to be replaced at something like 30K miles (it's a 36K now), as have both headlamps. The taillights go out so often I keep spare bulbs in the back.

    What are the odds this is really the skid control ECU and not some other, more global electrical problem. What to do next? Agh.

    Beth
     
  2. seilerts

    seilerts Battery Curmudgeon

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    The skid control ECU should NEVER need to be replaced unless the car has been in an accident or flooded.

    Have you had the inverter cooling pump replaced under the recall (announced 8 months ago)?

    Do you have the detail code on your paperwork for C1241? It would be a number 81, 82, 83 or 84. 83 points directly to the brake backup power supply (capacitors in the trunk next to the 12V battery). C1378 is incredibly rare, and I believe the service manual is wrong, as it states as a possible cause "malfunction in backup power supply" yet the trouble area is the skid control ECU.

    Take a look in the trunk at the backup power supply module and look for any obvious problems. For as often as tail lights have been replaced, perhaps the connector to it is loose.

    Blowing bulbs is definitely not normal. I think you should try a different dealership and hope for getting a more competent technician.
     
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  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    My 2007 had DTC C1247 back in 2008. First the dealership cleared the DTC. When this reappeared, then they replaced the skid control ECU, 89540-47100.

    However, two months later the brake system had trouble again. This time, DTC C1245 was logged. The answer was to repalce the stroke sensor, 89510-47010, and that permanently solved the problem.
     
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  4. callibeth

    callibeth New Member

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    Thanks for your feedback. I'm getting the detail on the error codes and taking it to another place for 2nd opinion on Thursday. Will check back then.

    **edited to add:
    Make that Monday or Tuesday, whenever they can get to it :(
     
  5. callibeth

    callibeth New Member

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    A second diagnostic yields the same error codes and the second opinion confirms that the skid control ECU should be replaced. Argh.
     
  6. seilerts

    seilerts Battery Curmudgeon

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    Find an independent shop that will put in a salvage ECU. Tell us where you are and we can make suggestions. I worry a bit about this for you in that they could say, "we had to replace the ECU and the brake power supply."
     
  7. callibeth

    callibeth New Member

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    First, the car is barely out of warranty -- by just a few days, I think. I'm going to look into whether Toyota will replace the unit under warranty since this has been a somewhat ongoing problem with the electrical system. I'd like to get salvage information if that doesn't happen. We're in north Florida.
     
  8. seilerts

    seilerts Battery Curmudgeon

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    It is a bit of a drive, but there is an independent hybrid specialist in Melbourne, Josh Mellor. mellorsautomotive.com

    Definitely pursue the warranty route, particularly if you have documented warranty work for the other electrical problems that you have experienced. I think your case is extremely unusual.
     
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  9. Hal W

    Hal W New Member

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    What about the stroke sensor as Patrick suggested? Hal