2004 gen II died on road. Code P0100 plz help

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by OHroadwarrior, Aug 12, 2012.

  1. OHroadwarrior

    OHroadwarrior Junior Member

    Joined:
    Mar 1, 2011
    6
    7
    0
    Location:
    OH
    Vehicle:
    2004 Prius
    Model:
    N/A
    My gen II died on the way home. I need some direction fast. Have tried the following... resetting codes (scanguage II will not let me see 2nd code it says is there). Pushing all connections into ECU etc under glove box area. Unhooking battery for 10 mins. Observed the following off the top of my head...

    red death, brake, trac control and yellow warning lights, fuel gauge shows full but flashing ( 5 gallons added post problem), after 10 min reset, hybrid battery goes from showing 1 pink to 4 or 5 blue, traction loss light goes out, brake light goes out, then goes back to 1 pink and "problem" shows up on screen after restart attempt. Engine does not even turn over. Car does not go into F/R, brake lights work.

    I appreciate any assistance/direction to avoid dealer costs.
     
    #1 OHroadwarrior, Aug 12, 2012
    Prius_Angie likes this.
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,200
    6,489
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    DTC P0100: Mass or Volume Air Flow Circuit. The likely suspects are the wiring harness and connector associated with the mass air flow sensor, the MAF sensor itself, and the engine ECU.

    I suggest you try removing the MAF sensor and cleaning it with MAF sensor cleaner. Do not use other solvents on the sensor. Check the wiring harness connector and the MAF sensor terminals for corrosion in the contacts and use the MAF sensor cleaner to clean if needed.

    If you have no idea what the MAF sensor is but want to DIY please do a search as many posters including me have posted regarding how to remove and clean it. Check the engine air filter while you are at it, and replace the filter if you cannot see light coming through when the filter is held up to sunlight. Good luck.
     
    #2 Patrick Wong, Aug 12, 2012
    Prius_Angie, dave77 and PriusCamper like this.
  3. 2009Prius

    2009Prius A Wimpy DIYer

    Joined:
    Mar 25, 2009
    2,705
    511
    63
    Location:
    USA
    Vehicle:
    2009 Prius
    #3 2009Prius, Aug 13, 2012
  4. OHroadwarrior

    OHroadwarrior Junior Member

    Joined:
    Mar 1, 2011
    6
    7
    0
    Location:
    OH
    Vehicle:
    2004 Prius
    Model:
    N/A
    I misspoke on the code. Posted entire outcome for all to refer too in future. Thx patrick, I cleaned that also, it took less than 10 mins to do.

    See link
    2004 gen II Code U0100 | PriusChat
     
    #4 OHroadwarrior, Aug 16, 2012
    Prius_Angie likes this.
  5. billywonkar

    billywonkar New Member

    Joined:
    Oct 15, 2022
    2
    0
    0
    Location:
    Georgia
    Vehicle:
    2006 Prius
    Model:
    N/A
    U0100 on my Prius was caused by a blown fuse. Filling with gas / unplugging the 12v battery did nothing. Had to leave car and walk home until morning when stores were open. My $20 oxygen sensor shorted and blew the top right, blue, 15 amp fuse. Any auto parts store and maybe Walmart will have a box of 15A Low Profile Mini Fuses for $5.

    Fuse box is top right of engine compartment under a black plastic top. Use pliers and maybe fingernails to pull out the colored fuses (yellow, red, blue, green). Hold the fuse flat, and look at the metal inside. If the metal makes a complete U shape, it's good. If the metal is two distinct pieces, it's bad. Once replacing, my car started and I went to the Toyota dealership to drop $180 on a legitimate oxygen sensor.

    ps. I unhooked my bad O2 sensor before replacing fuse. Also, different component failures may cause your U0100, so first check all your mini fuses.
     

    Attached Files:

    #5 billywonkar, Oct 15, 2022
(You must log in or sign up to post here.)