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HELP! Possible bad transaxle?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Kyle McDowell, Oct 9, 2020.

  1. Kyle McDowell

    Kyle McDowell Junior Member

    Joined:
    Mar 3, 2018
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    Location:
    Iowa
    Vehicle:
    2005 Prius
    Model:
    N/A
    I have a gen II 2005 Prius with the base trim. I noticed recently (as in 3 days ago) that the car makes what can almost be described as a howling noise when I lift off the gas pedal at any speed above 35. it sounds like there's an error in the regen braking. I also noticed that about 10 minutes after the noise started happening, the red triangle came on. Over the past few days, it sometimes is on with a brake warning light, and sometimes it's just the triangle. So I hooked it up to Techstream, prepared myself for the worst, and pulled a code P0A2B. Did some googling and it seems that other people with the same code had to replace their ECU and possibly (worst case scenario) the transaxle. Any thoughts on what it is/how to fix it? The car only has 100k miles on it and I got it about a month ago.
     
  2. SFO

    SFO Senior Member

    Joined:
    Feb 7, 2017
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    Location:
    Northern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Nice wheels you have there. Has the vehicle spent much of that mileage in or around the Iowa area?

    Check the mileage and maintenance history by entering the VIN at : Track Your Service Records with Your Toyota Owners Account

    Here is the repair workup for DTC P0A2B : https://share.qclt.com/%E4%B8%B0%E7%94%B0%E6%99%AE%E7%91%9E%E6%96%AF%E5%8E%9F%E5%8E%82%E8%8B%B1%E6%96%87%E6%89%8B%E5%86%8Cpdf%E6%A0%BC%E5%BC%8F/repair%20manual/04pruisr/05/21bpm/0a2b248.pdf

    Notice that the above DTC has two (2) INFs or subcodes, though not that helpful with this workup, knowing the INFs may help save on labor, parts or unnecessary expense. Techstream can also retrieve the three (3) digit INF, subcode, or 'detailed code'.

    Have you ever checked, or changed the ATF-WS in the transaxle assembly?

    Have you experienced any shuddering?
     
  3. edthefox5

    edthefox5 Senior Member

    Joined:
    Jul 25, 2007
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    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    MG reports overheat.

    That code sometimes logged if going up big mountain with low hybrid battery power and you keep flooring it for speed.
    Do you drive the car hard?

    Hows the hybrid battery health looking on the mfd charge wise. Goes to purple alot?
    And takes a while to get a blue bar or 2 back in it? Driving the car hard with poor battery health is very hard on the trans. Its a guaranteed way to blow a motor winding.

    I would:

    Check the inverter coolant is pumping good by making the car ready and open the cap to the inverter coolant reservoir and with a flashlight look inside at the fluid. Should look like its boiling meaning strong circulation.

    And like SFO says pull the trans fluid asap. before dumping it open the fill bolt and stick your finger in there and see if its low now. May have leak and is very low.
    Smell it for burn and look for metal debris on the dump bolt magnet.

    When you dump the fluid try to accurately measure it to see if it has been low. It takes almost 4 quarts.
     
    #3 edthefox5, Oct 10, 2020
    Last edited: Oct 10, 2020