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Car will not reverse.

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by RajivR74, May 23, 2019.

  1. RajivR74

    RajivR74 Junior Member

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    The car goes into forward & reverse gears but won't move in reverse. 'Check hybrid system' is on the display & I'm getting trouble codes p0a40 & p0a41. These codes were there before but the car was driving normally after clearing them. Any help would be greatly appreciated!

    Posted via the PriusChat mobile app.
     
  2. Maarten28

    Maarten28 Active Member

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    I'm guessing the electric motors won't operate. Driving in reverse is done electric only.
    P0A40 - Drive Motor 'A' Position Sensor Circuit Range/Performance
    P0A41 - Drive Motor 'A' Position Sensor Circuit Low

    Possible causes:
    - Faulty Inverter with converter assembly
    - Faulty Hybrid vehicle generator assembly
    - Faulty Hybrid vehicle motor assembly
    - Wire harness or connector
    I'd say: take it to a Toyota shop to have it fixed.
     
  3. Dxta

    Dxta Senior Member

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    If you're comfortable, check on the transmission system, just below the air filter box.
    In some cars, the sensor might be positioned on top the transmission, or built inside it.
    If its built inside, replacing the transmission system is the solution.
    You could also check to see of rats have eaten any of the wire harness there.
     
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  4. ChapmanF

    ChapmanF Senior Member

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    The motor "position sensors", a/k/a resolvers, are located inside the transmission. You can see them and their theory of operation in Prof. Kelly's videos from Weber State University.

    But there's pretty much nothing to go wrong with the resolvers themselves. Much more likely something has happened with the low-voltage electrical connections to the transmission (the normal-looking wiring, not the orange cables). Rodents would be one possibility.
     
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  5. bisco

    bisco cookie crumbler

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    we're in gen 3 forum, is it the 2006?
     
  6. RajivR74

    RajivR74 Junior Member

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    No, it's a 2013.

    Posted via the PriusChat mobile app.
     
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  7. bisco

    bisco cookie crumbler

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    how many miles?

    have you owned since new?
     
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  8. RajivR74

    RajivR74 Junior Member

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    It's got almost 360k miles on it. It's not my car. I'm trying to work on it for a friend who drives for Uber & Lyft. It's his sole source of income & I'm trying to help him as best as I can.

    Posted via the PriusChat mobile app.
     
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  9. RajivR74

    RajivR74 Junior Member

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    It won't move at all in any direction now. Just a bad shuddering sound. Similar to what was happening when the car was turned off before.

    Posted via the PriusChat mobile app.
     
  10. bisco

    bisco cookie crumbler

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    try the online service manual. are you reading codes with tech stream?
     
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  11. RajivR74

    RajivR74 Junior Member

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    No. I'm reading them with the torque app on my phone paired to a very basic Bluetooth OBDII reader.

    Posted via the PriusChat mobile app.
     
  12. RajivR74

    RajivR74 Junior Member

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    Where would I find the online service manual? Do you have a link to it?

    Posted via the PriusChat mobile app.
     
  13. bisco

    bisco cookie crumbler

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    if you exhaust the possibilities laid out above without any luck, that might have to be the next step.
     
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  14. bisco

    bisco cookie crumbler

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    techinfo.toyota.com
     
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  15. RajivR74

    RajivR74 Junior Member

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    Thank you. I'm checking it now.

    Posted via the PriusChat mobile app.
     
  16. Mendel Leisk

    Mendel Leisk Senior Member

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    That is a lot! Has it been just basic maintenance up to know, mostly oil changes? It would be a minor miracle if the EGR is still functional.

    Guessing inverter coolant pump failure caused transaxle to burn out?

    I'll pm you a link.
     
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  17. RajivR74

    RajivR74 Junior Member

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    Yes, please. That would be great. Thank you very much!

    Posted via the PriusChat mobile app.
     
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  18. RajivR74

    RajivR74 Junior Member

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    Ok. I have no idea what happened but the car is operating normally now! All I did was let it sit for a couple of hours, turn it on & immediately shift into neutral to avoid the loud shuddering (almost grinding) noises. The ICE was charging the battery like it should. I cleared the trouble codes (P0a40 & P0a41), turned the car off & restarted it. It now drives forward & reverses like nothing was wrong with it! I have only done this in my driveway as I am afraid to take it out on the street. What do you guys think?

    Posted via the PriusChat mobile app.
     
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  19. bisco

    bisco cookie crumbler

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    could be what mendel said above. without the coolant pump working, the car will keep shutting down when it gets too hot
     
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  20. ChapmanF

    ChapmanF Senior Member

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