1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Yellow light flashing and beeping

Discussion in 'Gen 3 Prius Main Forum' started by southjerseycraig, Apr 6, 2017.

  1. southjerseycraig

    southjerseycraig Active Member

    Joined:
    Jan 23, 2009
    438
    107
    0
    Location:
    Cherry Hill, NJ
    Vehicle:
    2010 Prius
    Model:
    II
    In the past few weeks, the yellow light has been coming on from time to time (maybe twice in a 12-mile trip) and I have heard beeping. Strangely enough, this has been happening in dry weather. I don't detect any change in what the car is doing, but it's odd to have that light flashing and hearing the beep. Is this a sign my tires need to be replaced, or of something else -- or of nothing at all?
     
    #1 southjerseycraig, Apr 6, 2017
  2. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    23,278
    15,078
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV


    It would help some if you could describe which yellow light; there are more than one.

    It would help a lot to pull the diagnostic codes from the car using a suitable reader.

    Your thinking seems to be running along the lines of stability or traction control. The computer that does that has a rudimentary way to blink out trouble codes when triggered by a short piece of wire. That will only show actual trouble codes, as in, if it really thinks there is a problem.

    If the control has just been activating under certain driving conditions and doing what it's supposed to, it won't log trouble codes. On the other hand, it does remember the last several (four, maybe?) times it activated, what was happening at the time, the power, all four wheel speeds, acceleration and cornering g forces, etc. That can be read out any time using Techstream. That might give you something to go on.

    -Chap
     
    #2 ChapmanF, Apr 6, 2017
  3. southjerseycraig

    southjerseycraig Active Member

    Joined:
    Jan 23, 2009
    438
    107
    0
    Location:
    Cherry Hill, NJ
    Vehicle:
    2010 Prius
    Model:
    II
    I am sorry not to have been clearer. I meant the yellow light on the left side of the instrument panel with the picture of the car slipping around the road.
     
    #3 southjerseycraig, Apr 6, 2017
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,703
    48,947
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    how are your tyres pressure? are all 4 tyres the same model?
     
    #4 bisco, Apr 6, 2017
  5. xliderider

    xliderider Senior Member

    Joined:
    Apr 19, 2012
    7,848
    3,102
    0
    Location:
    Honolulu, HI
    Vehicle:
    2011 Prius
    Model:
    Three
    Are you pulling fast u-turns, or accelerating rapidly through a sharp turn when the error light flashes? If yes, then it's the traction control detecting differences between the inside and outside wheel speed.
     
    #5 xliderider, Apr 6, 2017
  6. southjerseycraig

    southjerseycraig Active Member

    Joined:
    Jan 23, 2009
    438
    107
    0
    Location:
    Cherry Hill, NJ
    Vehicle:
    2010 Prius
    Model:
    II
    The pressures have been OK, but it's true that the four tires are not the same model. I had a flat several thousand miles ago, and the tire dealer insisted I only needed one tire and the model is different from the rest. . But the problem didn't start then.
     
    #6 southjerseycraig, Apr 6, 2017
  7. southjerseycraig

    southjerseycraig Active Member

    Joined:
    Jan 23, 2009
    438
    107
    0
    Location:
    Cherry Hill, NJ
    Vehicle:
    2010 Prius
    Model:
    II
    Thanks, but I'm doing neither of those things. I'm engaged in fairly normal driving. I'm a scaredy-cat and don't do anything exotic.
     
    #7 southjerseycraig, Apr 6, 2017
  8. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,703
    48,947
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    have you had the tires rotated recently?
     
    #8 bisco, Apr 6, 2017
  9. southjerseycraig

    southjerseycraig Active Member

    Joined:
    Jan 23, 2009
    438
    107
    0
    Location:
    Cherry Hill, NJ
    Vehicle:
    2010 Prius
    Model:
    II
    About 3000 miles ago, assuming the Toyota dealer did what it was supposed to. It sounds like you also think there is a tire issue here.
     
    #9 southjerseycraig, Apr 6, 2017
  10. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,703
    48,947
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    just guessing. no idea really, except i've read you should match tires on the axle, it can affect the speed sensor. i thought maybe moving the odd tire to the front might have caused a problem, but maybe not after 3,000 miles.
     
    #10 bisco, Apr 6, 2017
  11. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,703
    48,947
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    what speeds is it happening at?
     
    #11 bisco, Apr 6, 2017
  12. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,476
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    .
     
    #12 Raytheeagle, Apr 6, 2017
  13. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    23,278
    15,078
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    That's the exact kind of information that can be retrieved from the traction computer.

    -Chap
     
    #13 ChapmanF, Apr 6, 2017
  14. JimN

    JimN Let the games begin!

    Joined:
    Nov 26, 2006
    7,028
    1,116
    0
    Location:
    South Jersey
    Vehicle:
    2010 Prius
    Model:
    V
    Craig, I don't know if the light has stored a code that a ScanGauge will read but I'm close enough to take a look at the car. Send me a PM if you're interested.
     
    #14 JimN, Apr 8, 2017
(You must log in or sign up to post here.)