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2009 Check Engine light and Red Triangle Issue

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Chris Norris, Dec 5, 2017.

  1. Chris Norris

    Chris Norris New Member

    Joined:
    Dec 5, 2017
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    Location:
    Lakeland, FL
    Vehicle:
    2009 Prius
    Model:
    II
    Have 2009 Prius with about 80k miles on it. If i drive around town i have no issues, but when i drive on the interstate and get up to speeds around 70mph the check engine light, red triangle light, along with two other lights come on. Once i stop and let it sit and then restart, the check engine light and red triangle will remain on but other two go away. If then drive around town just a little and never get up to high speed and then park and wait and turn back on everything is gone. This will remain so until i drive again at high speeds in happens again, but only in the afternoon during more heat, mornings it is fine on the interstate (live in FL, so 50s in the morning and 70-80 in afternoon the past week or two when this happens). I have checked the fluid levels and it is fine, for radiator, electric motor fluid and reserve. So not sure what is causing this and how to fix it. Any help would be greatly appreciated.
     
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
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    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    welcome!

    could be the inverter pump, or maybe similar. why not read the trouble codes for a definitive finding?
     
    Raytheeagle likes this.
  3. fotomoto

    fotomoto Senior Member

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    Apr 22, 2009
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    Location:
    So. Texas
    Vehicle:
    Other Hybrid
    Check again with the car ON in ready mode and in P. You should feel vibrations in the hose leading the inverter coolant tank (the one on the right when standing in front of the car looking at the engine bay) or see coolant movement inside the tank. If not, the inverter pump has failed and needs replacing (common). Repair cost isn't too bad compared to many other issues and can be done by those who are mechanically inclined. Changing out the coolant would be good idea too since you're halfway there.

    If it's OK, you'll need to get the trouble codes read.