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

08' Random malfunction indicator lamp occurence

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by jhaas, Dec 26, 2011.

  1. jhaas

    jhaas New Member

    Joined:
    Dec 26, 2011
    3
    0
    0
    Location:
    SE Michigan
    Vehicle:
    2008 Prius
    Model:
    N/A
    I have an 08 prius with about 36k miles on it. Never had a problem other then getting the water pump replaced under warranty during scheduled maintenance.

    Today I drove about 10 minutes to get a haircut, was inside a half hour at most, came back, and the MIL was on. Never seen this before. Nothing appears to be wrong with the car when driving. I tried re-tightening the gas cap but that didn't seem to do anything, and it's been a week since I got gas anyway.

    I called my dealership and the service guy didn't sound too worried. He said a lot of stuff can cause that light and if the car is starting I should be fine. Said to bring it in if I notice anything going wrong.

    Any tips/ideas here? The only thing I noticed myself is that it seemed like the heat/air system was getting up to a warm temperature quicker than usual but the manual didn't indicate that the air system had anything to do with this warning light.

    EDIT: per jd's suggestion, I had the code read at AutoZone and it is a faulty oxygen sensor. Sounded like an inexpensive repair, but I'd still like some advice on what exactly this is, what happens if left untreated, approximate repair cost, etc/
     
    #1 jhaas, Dec 26, 2011
  2. jdenenberg

    jdenenberg EE Professor

    Joined:
    Nov 21, 2005
    3,837
    1,827
    1
    Location:
    Trumbull, CT
    Vehicle:
    2020 Prius
    Model:
    LE AWD-e
    Stop at Autozone and have them read the codes. Report the results here and one of us will interpret the codes properly (Autozone's interpretation is generic, not Prius specific).

    JeffD
     
    #2 jdenenberg, Dec 26, 2011
  3. edthefox5

    edthefox5 Senior Member

    Joined:
    Jul 25, 2007
    10,096
    4,795
    0
    Location:
    Clearwater, Florida
    Vehicle:
    2007 Prius
    Model:
    Two
    Your not specific which MIL is thrown. That's important.

    Pop the hood. Check the engine oil level. Then get a flashlight and check the engine coolant level in the reservoir above the rad. Then check the Inverter coolant level in the reservoir carefully. Then check the brake fluid reservoir.

    Then while the car is in "ready" open the cap of the Inverter coolant reservoir and make sure there is some good turbulence in the reservoir reflecting that the coolant pump is circulating that coolant. Should have some good coolant movement in that reservoir. Thats very important as its cooling the 2 most expensive things in that car. The transmission and the Inverter.

    Usually if a Prius throws a MIL there's an issue so don't disregard this like the dealer says.
     
    #3 edthefox5, Dec 26, 2011
  4. jhaas

    jhaas New Member

    Joined:
    Dec 26, 2011
    3
    0
    0
    Location:
    SE Michigan
    Vehicle:
    2008 Prius
    Model:
    N/A
    I don't remember the exact code that he read out, but he said it's a faulty oxygen sensor, "the first one in the system."

    and ed, it's the one that's valve-shaped? haha I'm not sure how to describe it, but that one with the word "check" underneath it.
     
    #4 jhaas, Dec 26, 2011
(You must log in or sign up to post here.)