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Abs, traction control and red and yellow brake lights all at once

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by d-one, Aug 25, 2014.

  1. d-one

    d-one New Member

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    I am hoping that someone can point me in a good direction:

    A few days ago I was driving no more than 20mph and the skid lights came on, it seemed like the engine or wheels lost power for about 10 seconds. After this, the yellow and red brake lights (!) came on as well as the abs and the traction control. I pulled over to take a quick look around and noticed that my left rear tire was nearly flat and so I filled it up with no effect. It seemed to drive perfectly fine after that but the lights stayed on. I took it to the dealer today, and after a frustrating $225 diagnosis only.....they had nothing to say except it could be any of 10 things and we will just start fixing them until we get the right one. I really don't want to spend $2000 fixing a $5000 car.

    The dealer gave the codes: C0215 LH rear speed sensor circuit malfunction, B1421 B1244, and C2318. The sensor resistance was tested "good" on each wire. They reset the lights and told me that my brakes were working fine (at least wouldn't fail) but the abs and traction control were not.

    Within 20 feet of pulling out of the lot, it happened again, same as the first time with the skid light coming on, loosing some traction/power then all the lights coming on.

    Their next recommendation is replace the skid control ecu. Is this something I can easily do myself? Is that likely the problem? Or does it sound more like the wiring?

    I also swear that I read some recall on this but the dealer said there was not one.

    Any feed back is appreciated.
     
  2. drysider

    drysider Active Member

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    It seems unlikely, but I would check the 12 volt battery first.
     
  3. d-one

    d-one New Member

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    Ok, should I just replace the 12 volt then? It does not seem like a likely candidate.
     
  4. dorunron

    dorunron Senior Member

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    I would check it (12 volt), but not replace it unless the voltage is not up to par.

    As Toyota said, it could be any number of things. Watch for a post from Patrick Wong. He is knowledgeable on the Gen II and can help you in this aspect. You may be correct that the ECU will need to be changed.

    It won't hurt to fully charge the 12 volt and reset the Prius (disconnect battery), but I believe the problem will still exist after that.

    Sorry I can't help you any more than that.

    Let us know what the final fix is.

    Best of luck to you,
    Ron (dorunron)
     
  5. bisco

    bisco cookie crumbler

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    how many miles on her?
     
  6. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Actually, this is a likely candidate because your car logged DTC C2318 which is a low voltage error logged by the transmission shift control mechanism. Start with that, or you can try charging the 12V battery first if it is less than four years old.

    Then if the car continues to log DTC C0215, have the speed sensor for the left rear wheel replaced. That is much easier and cheaper than replacing the skid control ECU which will require most of the dashboard and the steering wheel column to be removed for access.
     
  7. Jamshed

    Jamshed New Member

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    It may be the problem of ABS unit