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Check Hybrid System, P0A0F / P2111

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by shawn.ne, Jun 16, 2022.

  1. bisco

    bisco cookie crumbler

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    thanks for the update, glad they got you sorted! (y)
     
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  2. ilhouhou

    ilhouhou Junior Member

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    Hi Shawn, I have a 2010 prius gen 3. Having the error code of p0a0f and p2111 as well. For p2111, you can fix it by replacing the throttle body. What about p0a0f? This is caused by the fuel pump right? Did you fix it?

    Thanks
    Kris
     
  3. Brian1954

    Brian1954 Senior Member

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    Trouble code P0A0F is "engine failed to start", and P2111 is "Throttle actuator control system - stuck open". So both of these trouble codes could be caused by a bad throttle body.

    I would take off the air filter housing and inspect the throttle body. Is the throttle body valve open or closed with the car off? Is the throttle body dirty? Clean the throttle body, then disconnect the 12v battery for a reset, and then try to start the car.

    Come back and tell everyone if this solves the problem or not.

    Posted via the PriusChat mobile app.
     
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  4. ilhouhou

    ilhouhou Junior Member

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    Thanks a lot. I will give it a try and you posted.
     
  5. ChapmanF

    ChapmanF Senior Member

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    No, P0A0F is just a generic code from the power management control ECU (the orchestra conductor for the car).

    The P2111 comes from the engine control module, and tells you what the engine issue is.

    P0A0F is just the power management control ECU saying "I don't know what the issue is, but I cued the ECM to start the engine and he wouldn't do it, go ask him why."
     
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  6. ilhouhou

    ilhouhou Junior Member

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    Brian, I did exactly what you said, and watched a few youtube videos and cleaned the throttle body by myself. The car drives a bit differently, I think. The first time start after the job was rough, the whole car shook for a sec. Then it's all good now.

    The cleaning process is not as easy as the pros on youtube. I felt like I was damaging the throttle during the process. Luckily the car is working now and no code so far.

    Appreciate your help and encouragement again. Also a big thank you to ChapmanF.
     
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  7. ilhouhou

    ilhouhou Junior Member

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    Hi Brian, seems like the problem came back. I removed the throttle body this morning and cleaned it inside out. But the code is still there. The throttle valve is slightly open and not balance. TBH I have no idea what a normal throttle body valve looks like. Does it mean I have to replace it? Thanks.
     
  8. shawn.ne

    shawn.ne Junior Member

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    Sorry, I never saw this until now. Yes, replacing the throttle body and throttle position sensor solved the issue (both codes) and I have not had any related problems since then. That was about 110,000 miles ago.
     
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  9. Brian1954

    Brian1954 Senior Member

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    I would buy a used throttle body and see if that fixes the problem.

    Posted via the PriusChat mobile app.
     
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  10. ilhouhou

    ilhouhou Junior Member

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    Thanks, just replaced with a new throttle body bought online, cost about 120 Pound. Let's see how long can this last. Is throttle position sensor the MAF sensor BTW?
     
  11. ilhouhou

    ilhouhou Junior Member

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    I bought a new one that made in China, seems like the seller sold hundreds of it. Let's see how long it would last. Thanks.
     
  12. Brian1954

    Brian1954 Senior Member

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    No. The throttle position sensor is installed in the throttle body assembly.

    Posted via the PriusChat mobile app.
     
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  13. ilhouhou

    ilhouhou Junior Member

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    I have tried to search on youtube and ebay, can find onle one used throttle position sensor, is the part number 89451-47060? Where is this sensor in the car? thanks
     
  14. ChapmanF

    ChapmanF Senior Member

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    I suspect that eBay seller is just mistaken about what part that is.

    I think PNC 89451 would be a shift sensor, which that picture looks a lot more like:

    89451.png

    You would have the devil of a time attaching that to your throttle.
     
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  15. ilhouhou

    ilhouhou Junior Member

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    Thanks ChapmanF. Looks like this sensor is inside of throttle body?
     
  16. ChapmanF

    ChapmanF Senior Member

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    Right. Maybe don't get too hung up on the sensor? P2111 only means that the ECM tried to move the throttle to a more-closed position and it didn't go there (according to the sensor). So it could mean the sensor is bad and lying, or it could mean the sensor is just doing its job and telling you what didn't happen. It's good to check all the possibilities: make sure the throttle itself mechanically moves smoothly, the wiring is intact, and so on.