Prius won’t get over 30mpg after new engine installed

Discussion in 'Prius v Technical Discussion' started by Chardone69, Apr 29, 2021.

  1. Chardone69

    Chardone69 Junior Member

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    They are cheap on eBay. Make sure you don’t have a bad solenoid first. After popping another TCM I tested the solenoid and it was BAD. It was somehow back feeding and shorting the computer.
     
  2. TMR-JWAP

    TMR-JWAP Senior Member

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    Can you provide any details on this solenoid? I'm just not familiar enough to know if the Gen 2 is similar. trying to sort it out. Got a TCM from a 2009 salvage car for $18 over the weekend.
     
  3. ChapmanF

    ChapmanF Senior Member

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    Yes, please give some additional details, maybe even photos of the parts, or part numbers if you have them.

    The Transmission Control ECU has a pretty narrow job description: there is a single switched-reluctance electric motor that it drives in one direction to lock the transmission into Park, and drives in the other direction to shift out of Park. It has no other effect on how the transmission operates. (Those details haven't changed very much from Gen 2, but at least the actuator motor is now in a more accessible place on the tranny.)
     
  4. rjparker

    rjparker Senior Member

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    The "solenoid" must be the Shift Control Actuator Assembly that operates the Parking Pawl.
    EE81604B-3F34-4275-A6B8-BD38DFF3E26C.jpeg
     
  5. ChapmanF

    ChapmanF Senior Member

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    Yes, that's the switched-reluctance electric motor I mentioned. We might assume that's what Chardone69 is calling the "solenoid", if the Transmission Control ECU is also what Chardone69 is calling the "TCM".

    But that's why I asked if @Chardone69 could come back with photos or part numbers, so we don't have to assume. We already know Chardone69 has been told some things that weren't accurate (about gears and overdrive etc.). So the picure isn't quite fitting together perfectly, and that's a point in history-gathering where it helps to back up one step and say "ok, can you clarify exactly what parts you're talking about?".
     
    #85 ChapmanF, Jun 8, 2021
    Last edited: Jun 8, 2021
    Tim Jones likes this.
  6. TMR-JWAP

    TMR-JWAP Senior Member

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    Well, I wouldn't have believed it, if I hadn't just finished it........

    refer to post #77. This car has been kicking my BUTT trying to figure out the ticking noise on regen. No noise on acceleration or steady highway speed, just when coasting or on the brakes. Sounds just like a playing card in the spokes of a bicycle, and fairly loud. The frequency follows the speed of the car, yet completely goes away if you put car in neutral while coasting.

    This is the 2005 Prius we purchased in fall of 2018 with 195k miles on it. Now around 230k? Recently sold it (very cheap!!) to a previous forum member because he needed another car for the family, with the understanding there may be something wrong with the transaxle.

    He swung by the house today, we installed the 2009 TCM I bought recently for <20 bucks. Took 5 minutes, or less, to swap out. 2005 part number 89535-47010. 2009 part number 89535-47020. Exactly the same externally, at least. Guess what? The noise is completely gone. No more ticking. I still don't get it, but I'm a believer. And to think I spent $250 bucks on an axle/hub kit to replace both sides and spent an entire Saturday morning doing that, when all I really needed was a TC module and 5 minutes. Maybe this can save the next guy.

    We also disassembled the old tcm and there was NO obvious damage that jumps out and says "look at me".

    I'm still shaking my head over this one....dang I let that car go cheap, lol. Probably a 1/4 of what it would go for now....
     
  7. TMR-JWAP

    TMR-JWAP Senior Member

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    Additional update....reported mpg has gone from mid 20's to a current 40. I'll get in touch again at end of week to see how things are going.
    Still shaking my head wondering wth?
     
  8. Chardone69

    Chardone69 Junior Member

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    It’s actually the park shift solenoid. It’s the only major electrical component on the transaxle other then the inverter.
     
  9. Chardone69

    Chardone69 Junior Member

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    Car was running great until Tuesday early morning when the car symbol with the explanation point came on. The Hybrid System Warning light. Car was getting 44mph which is the most it’s ever gotten since I owned it. I had made an appointment with the local dealer to take care of the recalls and today added the warning light issue as the tow truck arrived. Will know more on Monday. This car has been a spur lemon since the day I bought it. Unlike my 2020 Camry hybrid. I love that Camry.
     
  10. ChapmanF

    ChapmanF Senior Member

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    There is no such component. What you are calling a "solenoid" here is a switched-reluctance electric motor, which rotates through cycloid reduction gearing to move the parking pawl into and out of position.

    Solenoid:

    [​IMG]

    Switched reluctance motor:

    [​IMG]
     
    #90 ChapmanF, Jun 17, 2021 at 2:16 PM
    Last edited: Jun 17, 2021 at 2:27 PM
  11. jzchen

    jzchen Senior Member

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    Got any codes for us???
     
  12. Tim Jones

    Tim Jones Active Member

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