1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Anyone know how many screws hold the HV ECU?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by numba41, May 11, 2014.

  1. numba41

    numba41 Junior Member

    Joined:
    May 3, 2014
    42
    8
    0
    Location:
    Ashburn, VA
    Vehicle:
    2006 Prius
    Model:
    N/A
    Hi - I'm attempting to remove my bad HV ECU (Hybrid Control Module) from under the dash. I removed the two front bolts but can't tell what else is holding it. Can anyone help? Thanks in advance for any responses.
     
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,200
    6,479
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    You need to disassemble most of the instrument panel first, including the passenger-side airbag located in the large black plastic panel over the glove compartment. Then remove the engine ECU. The hybrid vehicle ECU has two nuts securing it, on brackets above and below the ECU.

    Consult techinfo.toyota.com for more details regarding this disassembly.
     
  3. numba41

    numba41 Junior Member

    Joined:
    May 3, 2014
    42
    8
    0
    Location:
    Ashburn, VA
    Vehicle:
    2006 Prius
    Model:
    N/A
    Patrick - Do you know if the hybrid ECU is plug and play or needs to be reprogrammed by Toyota? Thanks.
     
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,200
    6,479
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    It does not need to be programmed.

    I am wondering what causes you to think that the ECU has to be replaced.
     
  5. numba41

    numba41 Junior Member

    Joined:
    May 3, 2014
    42
    8
    0
    Location:
    Ashburn, VA
    Vehicle:
    2006 Prius
    Model:
    N/A
    Just replaced the 12V battery as I'm trying to diagnose the warning lights. Got code P0A1D and three U communication codes using Torque. I don't have the Toyota DTC but most DTC's for P0A1D point to replacing the Hybrid Control Module. The display that shows the ICE and Hybrid motor goes in an out but it doesn't appear that the HV battery is not charging properly.
     
  6. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,200
    6,479
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    I agree that DTC P0A1D generally will point to a failed hybrid vehicle ECU.