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Replacing Transmission and engine.

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by mypriuscious, Mar 3, 2022.

  1. mypriuscious

    mypriuscious Member

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    My engine blew a rod last week and my high mileage 2010 Prius is getting it's second engine. My question is are there any extra parts that should need to be replaced between the engine and transmission?

    What happened was I was accelerating on the highway to pass someone and the engine began to rev very high but there was no acceleration and some white smoke. Because of the free revving I thought that it was the transmission. My Second question is if anyone has an idea of what may have cause the failure?
     
    #1 mypriuscious, Mar 3, 2022
  2. JC91006

    JC91006 Senior Member

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    How high is the mileage? On these Turd Gen cars, the Engine and transmission replacements are very straight forward and should be done together, they both get dropped down together.

    There are more and more people having brake accumulator/actuator failures on these cars. So if you haven't replaced that yet, you might want to tackle that while everything is out of the way (another $1300 in parts).
     
    #2 JC91006, Mar 3, 2022
  3. mypriuscious

    mypriuscious Member

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    there was about 335k on that motor. Used 85k and I put 250k on it.
     
    #3 mypriuscious, Mar 3, 2022
  4. mypriuscious

    mypriuscious Member

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    After having replaced everything these are the codes we are seeing. The car will go into neutral and reverse, but not drive. Any help or guidance would be greatly appreciated.
     

    Attached Files:

    #4 mypriuscious, Apr 5, 2022
  5. ChapmanF

    ChapmanF Senior Member

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    Double-check that all the low-voltage (not orange) multiwire connectors are properly reattached to the transaxle. That's where those position sensor signals come from.
     
    #5 ChapmanF, Apr 5, 2022
  6. mypriuscious

    mypriuscious Member

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    Does anyone have the manual for these two codes P0A40 and P0A41? Or is there somewhere I can download it?

    Also, is the techstream scanner that you use a pc with more capable than an Autel high end scanner? Do you have a recommended brand of techstream if it is better than the Autel?
     
    #6 mypriuscious, Apr 28, 2022
  7. Mendel Leisk

    Mendel Leisk Senior Member

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    I believe I've got every Repair Manual mention of those two, in attached:
     

    Attached Files:

    #7 Mendel Leisk, Apr 28, 2022
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  8. mypriuscious

    mypriuscious Member

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    Thanks for responding so quick. I appreciate it very much! question about the pdf, what does it mean when the text is in blue? It seems like a hyper link, but when I click it does not go anywhere.
     
    #8 mypriuscious, Apr 28, 2022
  9. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah blue links are broken. If you search for the exact text adjacent to the link it usually gets you to the same place, eventually.

    if some wizard has ideas regarding repairing the links…
     
    #9 Mendel Leisk, Apr 28, 2022
  10. mypriuscious

    mypriuscious Member

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    Would you happen to know what part number is the low voltage wiring harness for the transmission?
     
    #10 mypriuscious, Oct 4, 2022
  11. ChapmanF

    ChapmanF Senior Member

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    Not a separate harness; those connections are just part of the engine wire harness.

    A couple different part numbers for 2010. A dealer might be able to say which one is yours, from the VIN:


    2010 Toyota Prius Wire, engine. Room, connector, clamp - 8212147111 - Genuine Toyota Part



    2010 Toyota Prius Wire, engine. Room, connector, clamp - 8212147113 - Genuine Toyota Part


    There should be a white plastic-tape tag attached to the harness somewhere with the number on it. I thought I had drawings indicating where on the harness the tag is, but I'm not finding those at the moment.
     
    #11 ChapmanF, Oct 4, 2022
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  12. mypriuscious

    mypriuscious Member

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    Thank you for your response! Is it possible that both harnesses work with my car? I ask because both come up in my search on my local Toyota dealers website and when I open each ones page they say they fit based on my VIN. I know it seems like a redundant question, but I want to be certain.
     
    #12 mypriuscious, Oct 5, 2022
  13. ChapmanF

    ChapmanF Senior Member

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    If the question is "is it possible?" I'm sure the answer is yes.

    If the question is "should I bet nine benjamins on it?" my answer is "I'm sure I don't know."

    Umm, why are you asking, exactly? Is there some damage to it near those tranny connections?

    It's often more cost-effective to repair a harness than to replace the whole thing. There are a bunch of connections and anchors to fuss with in replacing it.

    On the other hand, maybe those MG resolver connections are shielded, which might complicate repair.
     
    #13 ChapmanF, Oct 5, 2022
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  14. Elektroingenieur

    Elektroingenieur Senior Member

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    The dealers’ websites don’t always translate all of the information in Toyota’s Electronic Parts Catalog database. From the VIN in the scanner picture shared above, your car was built in October 2009, and the part number for the WIRE, ENGINE is 82121-47110, which has been superseded as a service part by 82121-47111.

    That said, before ordering a wire harness, especially as a new part from a dealer, I’d suggest to do the troubleshooting described in the Repair Manual (more info) first, to be sure that the problem is actually in the harness and not just a loose connector or a fault in the replacement transaxle.
     
    #14 Elektroingenieur, Oct 5, 2022
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  15. nicoj36

    nicoj36 Active Member

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    If it aint broken don’t fix
     
    #15 nicoj36, Oct 6, 2022
  16. ChapmanF

    ChapmanF Senior Member

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    I guess if something warn't broke, mypriuscious wouldn't be asking.
     
    #16 ChapmanF, Oct 6, 2022
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  17. mypriuscious

    mypriuscious Member

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    Originally, I was going to buy a used harness and then undo the tape on the harness and do the same to the original harness and swap the looms that go from the transmission to where it plugged in. But I wasn't sure I would be buying the correct harness(kinda why I asked). I also wasn't sure where the opposite end of the transmission harness plugged into, like into the cabin through the firewall or somewhere in the engine bay. Where I could very easily check resistance on each strand of wire that goes to the opposite end of the harness loom, and either replace or fix that wire. I drive about 50k miles a year. I have two vehicles, a Prius(my normal daily) and a Land Cruiser, one gets 43mpg the other gets 12mpg. I do think you are right about the cost. I'm just trying to gain more knowledge so I can sort this out appropriately and get my vehicle back on the road.

    I wanted to make sure I thanked you for clearing up the part number specifically! Thank you! And yes, you are right about diagnosing it properly.
     
    #17 mypriuscious, Oct 10, 2022
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  18. mypriuscious

    mypriuscious Member

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    I want to thank all those that helped me with information. It was very much appreciated. The car is now running again with a new used transmission.
     
    #18 mypriuscious, Dec 10, 2022
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