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vsc,abs and circle warning lignts on

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by cdsjklee, Mar 7, 2009.

  1. cdsjklee

    cdsjklee New Member

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    Hi
    I have 2007 prius lately vsc,abs and (circle)yellow, 3 warning lights on
    it turns on while I was driving and when I turn off the car and turns back on it usually turns off. but today it turns on and off by it self while i was driving. Does anyone had similar problem anyone know hot to fix it.

    thanks :(
     
    #1 cdsjklee, Mar 7, 2009
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    How many miles on the odometer? Have you checked your tire pressure?

    If your tire pressure is correct and the lights still come on, then I suggest that you visit your dealer for diagnosis. This might be a problem with the skid control ECU, or a problem with the inverter cooling pump not working and the 12V bus voltage sagging.

    In any event this should not be ignored as non-functional ABS and VSC constitute a safety issue.
     
    #2 Patrick Wong, Mar 7, 2009
  3. cdsjklee

    cdsjklee New Member

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    The circle warning light is not the tire warning light. and when those lights are on car brakes fine. The abs,vsc and the other warning lights comes on and off by itself when car is moving.
     
    #3 cdsjklee, Mar 7, 2009
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I suppose you are referring to the brake warning light that has an exclamation point inside a circle, with ( ) surrounding the circle. When that light goes on this means that the brake system is impaired.

    Although you say the car "brakes fine", if you had an emergency situation where you needed the ABS or VSC to work and those lights are on, then you would find that those systems would not be available to assist you. I again suggest that you visit your Toyota dealer so that diagnostic codes can be read and a diagnosis developed. Good luck.
     
    #4 Patrick Wong, Mar 8, 2009
  5. cdsjklee

    cdsjklee New Member

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    Can those warning lights check with obd II scanner.
     
    #5 cdsjklee, Mar 8, 2009
  6. jayman

    jayman Senior Member

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    If it's a problem with the braking system, you will need the Toyota scantool. As a heads up, never ever attempt to bleed the brakes on the Prius yourself, it cannot be done without the scantool
     
    #6 jayman, Mar 8, 2009
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

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    If you have an OBD-II scanner that is compliant with the Toyota CAN, you could try it and see. It probably won't retrieve codes produced by ECUs other than the engine and hybrid vehicle.

    Since you have brake, ABS and VSC warning lights on, the skid control ECU is the one that is likely producing DTC. The hybrid vehicle ECU may also be producing DTC and if you can obtain those codes, that might give you a hint.
     
    #7 Patrick Wong, Mar 8, 2009
  8. Mike Dimmick

    Mike Dimmick Active Member

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    Worst case scenario is that the Skid Control ECU has completely given up on computer-controlled braking and you're down to just braking the front wheels, with no assistance, using the hydraulic friction brakes only. Braking performance is seriously impaired in this case.
     
    #8 Mike Dimmick, Mar 8, 2009
  9. Skwyre7

    Skwyre7 What's the catch?

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    This sounds similar to when my brake light switch needed to be replaced. Here's that thread. Just a guess...
     
    #9 Skwyre7, Mar 9, 2009
  10. pleax

    pleax New Member

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    Has anyone changed a Skid or ABS ECU on one of these?
    Does anyone know where it is, or if there's any issues putting in another one from another Prius ?
    I might have to change mine ?
     
    #10 pleax, Apr 7, 2010
  11. atoeli

    atoeli New Member

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    Pleax, did you ever get your issue resolved?
     
    #11 atoeli, Dec 21, 2011
  12. valsor

    valsor Junior Member

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    Yes, I have replaced it on my 2nd gen. Lights gone afterwars.
     
    #12 valsor, Feb 21, 2020
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