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

Emissions test failed due to CEL bulb

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by sbddude, Dec 4, 2018.

  1. sbddude

    sbddude Junior Member

    Joined:
    Nov 1, 2012
    62
    10
    0
    Location:
    Bay Area, California
    Vehicle:
    2013 Prius v wagon
    Model:
    Five
    Today I took my 2010 in for a Smog check. It passes everything except the CEL bulb is out. I also don’t see it come on when first starting the car.


    Possibly related - I recently had the 12v battery disconnected for an hour, then drove 700 miles in one day. Only a few miles driven since then. The car otherwise drives fine.

    Any suggestions?
     
    #1 sbddude, Dec 4, 2018
  2. tankyuong

    tankyuong Senior Member

    Joined:
    Nov 9, 2012
    1,555
    660
    0
    Location:
    Central MO
    Vehicle:
    2012 Prius c
    Model:
    II
    Try unplugging your maf sensor and starting your car. See if it lights up
     
    #2 tankyuong, Dec 4, 2018
    m.wynn likes this.
  3. sbddude

    sbddude Junior Member

    Joined:
    Nov 1, 2012
    62
    10
    0
    Location:
    Bay Area, California
    Vehicle:
    2013 Prius v wagon
    Model:
    Five
    Unplugged MAF sensor, no CEL light. I verified the codes when unplugged with a Bluetooth OBD dongle.
     
    #3 sbddude, Dec 4, 2018
  4. tankyuong

    tankyuong Senior Member

    Joined:
    Nov 9, 2012
    1,555
    660
    0
    Location:
    Central MO
    Vehicle:
    2012 Prius c
    Model:
    II
    That’s rare unless someone before you unplugged or destroyed it
     
    #4 tankyuong, Dec 5, 2018
  5. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,661
    38,205
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Someone's got to say it, probably not but anyway: check for black electrical tape on the display?
     
    #5 Mendel Leisk, Dec 5, 2018
    Bay Stater and KK6PD like this.
  6. sbddude

    sbddude Junior Member

    Joined:
    Nov 1, 2012
    62
    10
    0
    Location:
    Bay Area, California
    Vehicle:
    2013 Prius v wagon
    Model:
    Five
    I ended up taking it to the dealer. It was a missing (not blown) 7.5 A "Meter" fuse. I suspect the smog shop tampered with it so it would fail and I would have to pay anyway. I don't have proof, though. I can't think of any other reason why a fuse would entirely be missing.
     
    #6 sbddude, Dec 7, 2018
    Mendel Leisk likes this.
  7. padroo

    padroo Senior Member

    Joined:
    Jan 11, 2008
    2,763
    2,250
    13
    Location:
    Chesterton, Indiana Another third world country.
    Vehicle:
    2016 Prius
    Model:
    Four
    Our emissions test in Indiana are run by the state and there is no charge. Only two counties have emission testing and I live in one of them.
     
    #7 padroo, Dec 8, 2018
  8. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,464
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Do you know for a fact that the CEL light would light up when the car was IG-ON, prior to your taking the car for the emissions test?
     
    #8 Patrick Wong, Dec 8, 2018
  9. sbddude

    sbddude Junior Member

    Joined:
    Nov 1, 2012
    62
    10
    0
    Location:
    Bay Area, California
    Vehicle:
    2013 Prius v wagon
    Model:
    Five
    No, it's something I didn't pay attention to.
     
    #9 sbddude, Dec 16, 2018
  10. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,661
    38,205
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Are you first owner? If not, maybe someone else removed the fuse, to try to pass a test in the past?
     
    #10 Mendel Leisk, Dec 16, 2018
  11. sbddude

    sbddude Junior Member

    Joined:
    Nov 1, 2012
    62
    10
    0
    Location:
    Bay Area, California
    Vehicle:
    2013 Prius v wagon
    Model:
    Five
    I've thought about that, but it passed smog 2 years ago. I've owned the car for 5 years. Maybe the smog place last time missed it?
     
    #11 sbddude, Dec 16, 2018
    Mendel Leisk likes this.
  12. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,464
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Looking at the electrical wiring diagram, I found a 7.5A MET fuse which provides power to the LED that is the check engine light. This is a change from 2G where a different fuse provided power to the CEL plus many other systems.
     
    #12 Patrick Wong, Dec 16, 2018
    Last edited: Dec 16, 2018
(You must log in or sign up to post here.)