1. Welcome to Tacoma World!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tacoma discussion topics
    • Communicate privately with other Tacoma owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

P0031/P0051 Fix

Discussion in '2nd Gen. Tacomas (2005-2015)' started by wlmuncy, Apr 27, 2010.

  1. Apr 27, 2010 at 5:14 AM
    #1
    wlmuncy

    wlmuncy [OP] Well-Known Member

    Joined:
    Mar 9, 2010
    Member:
    #32838
    Messages:
    787
    Gender:
    Male
    First Name:
    William
    Knoxville, TN
    Vehicle:
    2007 Double Cab Manual 4*4
    I posted a thread about my "new" truck purchase. In that I mention the problem I was having with getting P0031 and P0051 error codes. Now I am posting the fix (in my case at least). If anyone else gets both codes at the same time.

    1) I grabbed the FSM from this thread. http://www.tacomaworld.com/forum/2nd-gen-tacomas/89275-05-tacoma-repair-manual.html

    2) Found the section for my error codes.

    3) Followed it down to the place where both codes meet (AF Heater Relay).

    4) Found where the in cabin relay box was located. (Picture below behind the battery).

    5) Found the correct relay for the AF Heater- Pulled it out. Man It's a bitch I tell you. In the picture below the AF Heater relay is circled red.

    6) Pulled the Fog lamps Relay circled in gray (I tested this one an it was good- fog lights worked)

    7) Switched them.

    8) Restarted truck. No CEL. No battery clear. Truck is suppose to clear the CEL after start up once condition is cleared.

    9) Drove around. Restarted a dozen more times. No CEL.


    Hope this helps you.

    IMAG0006.jpg
    IMAG0005.jpg
     
  2. May 24, 2010 at 8:28 PM
    #2
    tonkatoy

    tonkatoy Well-Known Member

    Joined:
    Nov 1, 2009
    Member:
    #25290
    Messages:
    45
    Gender:
    Male
    First Name:
    Billy
    Phoenix, AZ
    Vehicle:
    08 White TRD Sport Acc 4x4 6 spd
    Thanks for posting the code and solution...
    I just got this code today. Did you replace the upstream
    o2 sensors first? I thought this code was to just change out the sensors. Why did you end up changing out the relays?

    Thanks,
     
  3. May 25, 2010 at 5:45 AM
    #3
    wlmuncy

    wlmuncy [OP] Well-Known Member

    Joined:
    Mar 9, 2010
    Member:
    #32838
    Messages:
    787
    Gender:
    Male
    First Name:
    William
    Knoxville, TN
    Vehicle:
    2007 Double Cab Manual 4*4
    The relay test was less expensive (free) and once it was corrected the codes went away. I have not had them again since. The reason I did not just replace the O2 sensors is I found it odd both would go out at the exact same time, also when I had the code read, the guy at the autoparts place thought it odd as well. So the relay was the common meet me place for both of these.
     
  4. May 26, 2010 at 9:44 PM
    #4
    tonkatoy

    tonkatoy Well-Known Member

    Joined:
    Nov 1, 2009
    Member:
    #25290
    Messages:
    45
    Gender:
    Male
    First Name:
    Billy
    Phoenix, AZ
    Vehicle:
    08 White TRD Sport Acc 4x4 6 spd
    Of course, two wouldn't go out at the same time. Genious! You just saved money for two sensors that you wouldn't been able to return. I have just trouble code P0031. Not P0051. I just wish I knew which side of the engine it is on. The repair manual doesn't say. Just says upper and lower.

    Does anyone know?
     
  5. May 26, 2010 at 10:04 PM
    #5
    BeefTaco

    BeefTaco WESTern Alliance: NORCAL COAST

    Joined:
    May 8, 2008
    Member:
    #6481
    Messages:
    631
    Gender:
    Male
    Santa Cruz County Ca.
    DTC
    P0031
    Oxygen (A/F) Sensor Heater Control Circuit Low (Bank 1 Sensor 1)


    HINT:
    • • • •
    Bank 1 refers to the bank that includes cylinder No. 1. Bank 2 refers to the bank that does not include cylinder No. 1. Sensor 1 refers to the sensor closest to the engine assembly. Sensor 2 refers to the sensor farthest away from the engine assembly.

    1GR-FE
    http://www.ncttora.com/fsm/05+/data/ileaf/06toyrm/06toypdf/06rmsrc/rm2006ta/0050015.pdf
     
  6. Apr 7, 2011 at 3:36 PM
    #6
    toytaco1

    toytaco1 Well-Known Member

    Joined:
    Mar 7, 2010
    Member:
    #32748
    Messages:
    85
    Gender:
    Male
    First Name:
    jed
    moreno valley
    Vehicle:
    05 supercharged trd off road
    trd supercharger, TRD intake, magna flow exhaust, JBA headers, walker evans front, fox rear, leaf pack, drilled slotted rotors, All Pro Front Bumper, Warn 8000 Winch
    I just popped 5 codes p0031 p0051 p0037 p0057 and p0430
    and this is after I had trouble starting the truck would the efi cause these codes to all come up at the same time? Also the truck has no power like it is in limp mode, it ran fine then all of a sudden it started to run really bad any help would be appreciated
     
  7. Apr 7, 2011 at 3:56 PM
    #7
    wlmuncy

    wlmuncy [OP] Well-Known Member

    Joined:
    Mar 9, 2010
    Member:
    #32838
    Messages:
    787
    Gender:
    Male
    First Name:
    William
    Knoxville, TN
    Vehicle:
    2007 Double Cab Manual 4*4
    Is there something in your exhaust pipe. None of those codes have anything to do with transmission issues which will put you in limp mode. All have to do with cat issues, but I would not think a failed cat would make the car limp, however, a stopped up exhaust system might.
     
  8. Apr 7, 2011 at 4:49 PM
    #8
    toytaco1

    toytaco1 Well-Known Member

    Joined:
    Mar 7, 2010
    Member:
    #32748
    Messages:
    85
    Gender:
    Male
    First Name:
    jed
    moreno valley
    Vehicle:
    05 supercharged trd off road
    trd supercharger, TRD intake, magna flow exhaust, JBA headers, walker evans front, fox rear, leaf pack, drilled slotted rotors, All Pro Front Bumper, Warn 8000 Winch
    Im gonna try and replace the af heater relay and see if that clears the symptoms, toyota said total cost would be over 4 thousand. The truck ran fine then within 24 hours started running the way it is, Im thinking that the cats are fine it only has 69k miles.
     
  9. Apr 7, 2011 at 6:37 PM
    #9
    toytaco1

    toytaco1 Well-Known Member

    Joined:
    Mar 7, 2010
    Member:
    #32748
    Messages:
    85
    Gender:
    Male
    First Name:
    jed
    moreno valley
    Vehicle:
    05 supercharged trd off road
    trd supercharger, TRD intake, magna flow exhaust, JBA headers, walker evans front, fox rear, leaf pack, drilled slotted rotors, All Pro Front Bumper, Warn 8000 Winch
    I did what you did and replaced the air fuel relay and cleared up the problem, tjanks for the post saved me some major dough
     
  10. Feb 18, 2014 at 6:33 AM
    #10
    tacoma73

    tacoma73 New Member

    Joined:
    Feb 18, 2014
    Member:
    #123381
    Messages:
    1
    Gender:
    Male
    Vehicle:
    06 Tacoma
    I also had error codes P0031 and P0051. After reading this post, I replaced the aforementioned AF relay and the CEL cleared (needed to disconnect battery to reset CEL).

    Thanks again.
     
  11. Feb 18, 2014 at 8:48 PM
    #11
    Jimmyh

    Jimmyh Well-Known Member

    Joined:
    May 16, 2012
    Member:
    #78991
    Messages:
    3,694
    Gender:
    Male
    SC
    Vehicle:
    Prerunner SR5

    He is referring to the fuel air mix " Limp Mode ". This is where the system stays in an Open Loop and will run like shit and consume gas like crazy but it will get you home, usually. The fuel system is not adjusting A/F Ratio to the feedback from the sensors.
     
  12. Apr 9, 2014 at 2:02 PM
    #12
    X moked U

    X moked U Well-Known Member

    Joined:
    Mar 3, 2013
    Member:
    #98864
    Messages:
    75
    Gender:
    Male
    URD ShortShifter/URD True Cold Air Intake/RedHydroshield/Magnaflow Exhaust/Doug Thorley Long Tube Headers/Vibrant Ultra Quiet Resonator/URD MAF CAL/Coupe Weighted Shift Knob/IKH20s/MT-90/Ultragauge/Evo Mod/Recessed Grill Mod/Red powdercoat devil horns/Painted X brace/Black wheels/Black Chrome Sport headlights w/6000k bi-xenon/Pioneer AVH-4500 appradio /avs-vent visors/Weathertech Mats/Hula Girl & some other crap
    This did not work on my truck :/
     
  13. Nov 24, 2014 at 4:24 PM
    #13
    jimbo808

    jimbo808 Well-Known Member

    Joined:
    Sep 5, 2012
    Member:
    #86337
    Messages:
    377
    Gender:
    Male
    Kapolei, Hawaii
    Vehicle:
    05 TRD Sport 4x4
    Debadged, Mbrp cat back turn down, Afe drop in filter, Icon extended travel, Light Racing ucas, Dakars, Icon 2.0 vs monotubes, Morimoto Minis D2S' bhlm with blacked out bowls, Bamf Sliders, pelfrey single hoop front bumper, pelfrey ifs skid, all pro rear with side plates, sway bar removed, front superbumps, Avec 20 inch light bar, rigid flood fogs
    i appreciate the guide, it got rid of my light :D.
     
  14. May 8, 2015 at 6:26 AM
    #14
    Scott Smith

    Scott Smith New Member

    Joined:
    May 8, 2015
    Member:
    #154841
    Messages:
    3
    Vehicle:
    2005 Tacoma double cab
    Thanks for the post on using the fog relay to test the heater relay. This worked for me and saved me many hours of trouble shooting. I picked up a new relay at the local ABC autoparts store and now everything works and the check engine light went off.
     
To Top