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

Faults PO420 (catalyst system efficiency below threshold) .

Discussion in 'Gen 3 Prius Main Forum' started by dgm1214, Sep 15, 2024 at 6:34 PM.

  1. dgm1214

    dgm1214 Junior Member

    Joined:
    Apr 10, 2023
    3
    1
    0
    Location:
    Wellman, iowa
    Vehicle:
    2013 Prius
    Model:
    III
    This popped up after replacing both oxygen sensors, on a 2013 with 177k miles. Prior error was related to faulty downstream oxygen sensor, and found wires from connector damaged. Did this work myself with sensors off Amazon, about $40 each.
    Wondering if I did something wrong ?
    Thanks !
     
    #1 dgm1214, Sep 15, 2024 at 6:34 PM
  2. dgm1214

    dgm1214 Junior Member

    Joined:
    Apr 10, 2023
    3
    1
    0
    Location:
    Wellman, iowa
    Vehicle:
    2013 Prius
    Model:
    III
    Update, reset codes again, and after 50 miles NO codes popped up. Will test drive tomorrow too.
     
    #2 dgm1214, Sep 15, 2024 at 9:25 PM
    bisco likes this.
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    109,518
    49,787
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    good luck!
     
    #3 bisco, Sep 16, 2024 at 2:09 PM
  4. dgm1214

    dgm1214 Junior Member

    Joined:
    Apr 10, 2023
    3
    1
    0
    Location:
    Wellman, iowa
    Vehicle:
    2013 Prius
    Model:
    III
    Update2. Drove only about 5 miles today before engine light appeared. Same 2 codes as before

    1) P0420 catalyst system efficiency below threshold Bank 1
    2) vehicle has no faults

    wondering why it says ‘no faults’ when it reported a P0420.
    Not sure if I should drive it on a trip, 700 miles one way into Canada, or not.
    Thanks for suggestions.
     
    #4 dgm1214, Sep 16, 2024 at 3:16 PM
    Last edited by a moderator: Sep 16, 2024 at 4:09 PM
(You must log in or sign up to post here.)