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'p' lock malfunction

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Mareno Rathell, Jan 3, 2016.

  1. Chuckx

    Chuckx New Member

    Joined:
    Dec 19, 2019
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    Location:
    Texas
    Vehicle:
    2005 Prius
    Model:
    III
    There is a problem with the transmission P lock mechanism Park your your car on a flat surface and fully apply the parking brake." with the red triangle

    My solution was passenger door handle malfunction l disconnected the good sized electrical plug behind the handle its self 2 screws whole door panel just pulls off a little force needed 5min fix

    Others possible causes listed...

    1. ToyotaPartDeal web site 33820 47020
    CABLE ASSY, TRANSMISSION CONTROL

    2. Transmission fluid Moisture build up was causing a high voltage leak error code P to engage error

    3. Transmission plug on park control motor being loose. reme plug and spray some contact cleaner. Then look for any likely spots for water getting in.

    4. Fuse number 34 is P CON MAIN fuse 7.5 amp Parking controlsystem, hybrid vehicle immobilizer system P Con Main fuse swap out worked triangle P lock error gone.
     
    #21 Chuckx, Dec 19, 2019
    Last edited by a moderator: Dec 21, 2019
  2. stephil

    stephil New Member

    Joined:
    Apr 27, 2020
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    Location:
    NH
    Vehicle:
    2013 Prius
    Model:
    Two


    this happens for me only when it rains. The message goes away after 20 minutes of driving. Any idea which of those causes could be the issue? For #2 would changing the transmission fluid be the fix?

    thanks!
     
  3. valde3

    valde3 Senior Member

    Joined:
    Jun 28, 2014
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    Location:
    Finland
    Vehicle:
    2004 Prius
    Most likely water gets in the parking motor or parking motor connection. Check the condition of that connector and clean it? Has the Prius been in a crash at some point? Or has transmission been moved or taken out during some big repair? Thous could have caused damage there. These problem can be caused with bad connection in 12V system so checking stuff ground cable and fuse boxes might be useful too. But that or bad/empty 12V battery only happening when it rains seems unlikely.

    Especially in your case this is not a problem as rain can't get in and effect trans fluid. But it's good idea to change the trans fluid for other reasons.
     
  4. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
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    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Even in a (relatively) simple subsystem like the transmission control ECU and parking actuator motor, there are still a number of different ways it can go sideways, and you can get useful information about what has happened a lot faster by plugging in Techstream and asking. It should have a freeze-frame available to show what voltages and conditions were at key places in the circuits at the time the last code was logged. Should point you in the right direction.