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Check Engine Light

Discussion in 'Gen 2 Prius Technical Discussion' started by jetsfan_00, Jul 6, 2008.

  1. jetsfan_00

    jetsfan_00 Junior Member

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    My 05 Prius with 75000 miles started to get check engone light in Jan. I continue to receive the light to date. I can clear the light by removing and replacing my gas cap. I have replaced the gas cap as well. Right now when I ckear the light, it will come back after a day or 2 and will not clear. It clears after I fill it up and only for a day or 2. No change in gas mileage, but having this light will cause the vehicle to fail emissions as my state goes by computer codes and not exhaust gases.

    I have talked with my shop and they can determine the error codes, but feel they could not repair. Need to go back to Toyota for a smoke test to fix any problems. This is becoming very common on most newer cars due to the E10 fuel being offered.

    Has anyone found a low cost solution? Or do I have to go to the dealer for a smoke test and cost for the repairs.
     
    #1 jetsfan_00, Jul 6, 2008
  2. bwilson4web

    bwilson4web BMW i3 and Model 3

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    What are the codes?

    Bob Wilson
     
    #2 bwilson4web, Jul 6, 2008
  3. jetsfan_00

    jetsfan_00 Junior Member

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    Bob,

    Can you help and tell me where this port is located? I have an analyer but do not know where this port is to plug it in.

    Cheers,

    Tim
     
    #3 jetsfan_00, Jul 8, 2008
  4. doubleg2005

    doubleg2005 Member

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    is this the same as the maint light? (probably not, eh?) the maint light can be cleared manually quite easily... if that were the case, i would say just clear it manually before the emissions test
     
    #4 doubleg2005, Jul 8, 2008
  5. ceric

    ceric New Member

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    Usually you can find the DLC-2 under the steering wheels.
    Any ScanGuage type of device allows you to see the codes and clear it if you wish to. Many AutoZone/Kragan shops are willing to read the codes for you for free.
     
    #5 ceric, Jul 8, 2008
  6. jetsfan_00

    jetsfan_00 Junior Member

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    No, i know how to reset the maintenance light. I have acontinuous check engine light and I cannot find the port to plug the analyer. Toyota claims it is directly under the steering colunm. I have not been able to locate any such port. If hidden, please give me a clue where it is.
     
    #6 jetsfan_00, Jul 8, 2008
  7. jdenenberg

    jdenenberg EE Professor

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    The OBD2 socket is behind a little door to the left and below the steering column (near your left knee when driving).

    JeffD
     
    #7 jdenenberg, Jul 8, 2008
  8. jetsfan_00

    jetsfan_00 Junior Member

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    I found the port. It was near my Right knee about an inch from the center console.

    The error code is P1121. What does this tell me?
     
    #8 jetsfan_00, Jul 8, 2008
  9. Patrick Wong

    Patrick Wong DIY Enthusiast

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    DTC P1121 "Coolant Flow Control Valve Position Sensor Circuit Stuck".

    The possible trouble areas include the coolant valve that controls the flow of engine coolant to the coolant heat recovery tank; a clog in the engine cooling system, or the engine ECU.
     
    #9 Patrick Wong, Jul 8, 2008
  10. jetsfan_00

    jetsfan_00 Junior Member

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    To all,

    Another site states this DTC Error Code P1121 for an 05 Prius is Accelerator Pedal Position Sensor Range/Performance Problem. In the past it cleared when I removed and replaced the gas cap. Now it is constant. Do you have other info to support DTC P1121 is "Coolant Flow Control Valve Position Sensor Circuit Stuck". Vehicle has had its coolant and CVT coolant replaced around 60K.

    Is the code Coolant or Accelerator?
     
    #10 jetsfan_00, Jul 8, 2008
  11. northwichita

    northwichita .

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    05 Prius ; Accelerator Pedal Position Sensor Range/Performance Problem.
    This is code P0121

    P1121 ; what Patrick Wong said
    "Coolant Flow Control Valve Position Sensor Circuit Stuck".

    The possible trouble areas include the coolant valve that controls the flow of engine coolant to the coolant heat recovery tank; a clog in the engine cooling system, or the engine ECU
     
    #11 northwichita, Jul 8, 2008
  12. archae86

    archae86 Member

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    The current edition of the Bentley Repair and Maintenance Manual for 2004 through 2008 Prius lists some Throttle/Pedal position sensor codes in the P2120 through P2138 range, including P2121--perhaps someone got a digit wrong.

    They list P1121 as Coolant Flow Control Valve Position Sensor Circuit Stuck, and suggest plausible trouble sites as the water valve itself, or clogging of the cooling system.

    You might want to review this TSB as additional evidence for the coolant interpretation of the P1121 code, and perhaps compare your VIN against the ranges they mention.
     
    #12 archae86, Jul 8, 2008
  13. jetsfan_00

    jetsfan_00 Junior Member

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    To all,

    I broke down and had the check engine light corrected. Dealer stated it was the relay on the coolant valve. Cost for part around $100, cost for repairs about $350. Now the good part. My dealer cut the labor in half, just by me asking. Maybe it does not take as long.

    I also called Toyota to see if I can get some help as it was issued as a TSB as a defective part and only covered under the original warranty. They initially said no, then called me back because it was a Pruis. This may have helped get a break on the labor. Next time you get a TSB part replaced see if you can a break on labor.

    It's been a week and no light.

    My white 05 Pruis package 2 (Dec 04 purchase).
    Miles travelled - 90K
    MPG to date - 46.1 mpg
    Maintenance to date - oil every 5K, transmission and engine Coolant @ 60K (same fluid for CVT and engine Coolant), second set of tires, 3rd set will be due soon, engine air filter every 10K and cabin air just done.

    Only issues are gas tank capacity/gauge verses mileage and speedometer is about 2-3 mph low. Compared to radar gun and GPS.
     
    #13 jetsfan_00, Sep 4, 2008
  14. richard schumacher

    richard schumacher shortbus driver

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    Thanks for the followup. It's good to know that it had nothing to do with E10 fuel.
     
    #14 richard schumacher, Sep 4, 2008
  15. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Thanks for the update. Could you please provide the part number and description of the replaced part, per your repair invoice?
     
    #15 Patrick Wong, Sep 4, 2008
  16. Clar

    Clar Member

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    My car has 62k miles on her and I've bought the platinum warranty from Troy. Does anyone know if the P1121 problem is covered under that warranty?

    Thanx.

    [update 1]

    I've sent the car in today and the platinum warranty covers the repair. dealer quoted me $500 something and about 2 hrs of repair time. I'll update thread w/ additional info once I get the car.

    [update 2]
    Got the car back. Warranty paid $328 for the work. part number and description are same as the ones in TSB
     
    #16 Clar, Sep 11, 2008
  17. Errel

    Errel New Member

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    Which dealership did you use? I am having problem with engine check light for my 05 Prius also. The code that showed was first P0121 then the next day it changed to P1121. I am thinking of bringing it to the dealership rather than my local mechanic.
     
    #17 Errel, Oct 23, 2009
  18. Sailshare

    Sailshare New Member

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    The Check Engine light came on, on our 2001 Prius after parking it without use for 2 months. Once we finished our short trip, turned it off, and back on the light wqas off and all worked fine. However thye nexdt time that we were out of the country for 2 months, we got the check engine light again but nit did not go off after repeatedly6 turning it off and on. We drove it without incident to the Toyota dealer and found that just one month after the warranty expired we had to replace the computer and and battery at a cost of $4300.
    Now the first time that we replaced the air filter the check engine light cxame on again. We checked the oil and found that we now hyave an oil leak, since we had to9 add 1/2 quart of oil a second time within 7 days.
    Anyone have a similar issue?
     
    #18 Sailshare, Nov 24, 2009
  19. donee

    donee New Member

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    Hi Sailshare,

    If you look around in the GENERATION ONE forums, you will find that is a common scenario with the generation ONE prius and there is no reason to post it here in the generation TWO prius forums. It needs a new Battery ECU, as the replacement batteries have a new generation module, which will last longer and not leak. The older generation modules are not made anylonger, because they LEAK.

    Believe it or not, the Prius was engineered by human being engineers. And as such they did not get everything as good as in the generation ONE prius as they have with the generation TWO prius.
     
    #19 donee, Nov 24, 2009
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