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2002 Prius DTC Code P3191

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by pmc2009, May 25, 2009.

  1. pmc2009

    pmc2009 New Member

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    DTC Codes P3191 Engine dose not start

    Let me tell you little bit what has brought me to this code. I bought this 2002 Toyota Prius little over a week ago at a car auction so it was sold as is with no warranty. And it ran great when I tested it no check engine lights or Triangles, engine was clean, sounded good, and oil and water looked good, so I turned down the extra cost to buy a contract cancellation option. Well I’m driving home from auction and I get close to home and all of a sudden red triangle &! With warning & Check engine light all come on so I freak out and pull over to side of freeway and start to look for anything that could be wrong, I don’t have my OBD2 scanner with me so I have no way to read the codes until I get the car home. Being new to a hybrid this triangle scared me and there is no engine temp gauge, So I’m thinking it over heated, So I wait 45 minutes to let the car cool down check all the fluids all looks good. So I proceed to drive it home about a block away from home I stop for a red light and light turns green and it stalls. So now I try starting it again it starts and I get home. So I hook up my obd2 scanner and get these codes P3125 SMR Assy Malfunction and P3130 HV Transaxle assy malfunction, so since I’m new to hybrids I go online to justanswers.com ask what the most common items that need fixing when these code come on. This certified Toyota mechanic wrote me back sending me Technical service bulletin (TSB) for both P3130 and P3125 So I read the TSB’s and it tells me to check water flow in inverter reservoir and check for kinks or blockages in hoses, I determine that that the Inverter electric water pump is not turning on, TSB instructs to replace water pump so I do, It also note that if DTC P3125 (converter and inverter malfunction) may also be present as a result of DTC P3130 do not Diagnose the P3125 DTC. I ignore P3125 as TSB says. Since I have the pump off, I flush the cooling system to make sure everything is flowing ok, then I install water pump, refill with coolant and bleed as instructed, I perform initialization procedure as manual says to do when aux battery is disconnected. Then I turn key to on position, check engine light and triangle are gone, ready light comes on so I started the car, the gas engine starts up runs for about 1-2 minutes and sounds smooth, then it just dies and sound a little rough as it stalls I looked up at the dash when it died and notice gas level very low and Triangle and Check engine light has returned, So I filled up tank, it at ¾ now, and find DTC code P3191, My Innova 3100 scanner says P3191 Cruise control Vehicle sensor malfunction and The Haynes manual says DTC P3191 Engine does not start, but I go online and double check code I read on one web site that it could mean HV ECU need replacing but on another web site that it could mean it out of gas, so I try starting again gas engine starts runs for 1-2 minutes then stalls I try this a few times sometimes the screen in center of dash flickers as it stalls and sometimes it does not. I tried stepping on gas petal thinking maybe it needs more gas, no response what so ever, engine does not rev up no matter if it during the 1st minute when engine is running fine or when It is about to stall. Also I went on to Toyota.com and looked up the repair history on this car and on 12-04-07 this car was in Toyota shop for codes P3191 & P3101 and dealer replaced relay, tank sub-assy, fuel and computer engine control. Sorry to make this so long but want you to know all the details so we can figure this out, and get the right parts because I am on a very low budget, when the 1st codes came up Toyota gave me a estimate of $4065.00 after just buying this car a week ago I have very little funds left to repair it, So I would appreciate any help I can get to fix this myself. What should I check, unfortunately I do not have a Toyota scan tool only a generic Inova 3100. Please if you could help with some advise as to what will fix the problem with the car it would be greatly appreciated.

    Thank you,
    Paul
     
  2. tochatihu

    tochatihu Senior Member

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    The engine control computer was already replaced you say, removing the most common cause for 3191. It would be grasping at straws to suggest that an early part number computer was replaced (instead of the ...54 you want).

    I understand that you have done some work now in the coolant system, and apparently you know there are 2 independent systems. The coolant flow to the inverter is now really good, right? Out of curiousity what color fluid are we looking at?

    Dogfriend's history of related reports reminds of that incorrect engine oil viscosity (too thick) is not what the Prius likes. No tellin' what's in there now.

    DTC-confusion in Prius often leads to 12 volt battery replacement oro at least cleaning up the electrical contacts. It helps more often than one might imagine.
     
  3. pmc2009

    pmc2009 New Member

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    I understand that you have done some work now in the coolant system, and apparently you know there are 2 independent systems. The coolant flow to the inverter is now really good, right? Out of curiousity what color fluid are we looking at?

    pink

    Dogfriend's history of related reports reminds of that incorrect engine oil viscosity (too thick) is not what the Prius likes. No tellin' what's in there now.

    I'm not sure ? but I should do an oil change just in case.
     
  4. tochatihu

    tochatihu Senior Member

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    Pink in both plastic reservoirs? Then I guess you have SLLC in both. Does the flow in the inverter reservoir look good with Prius in 'ready"?
     
  5. pmc2009

    pmc2009 New Member

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    I want to thank everyone who responded, The Triangle of death is gone as well as check engine light. And the car so far stays running and doesn’t stall.
    1.[FONT=&quot] [/FONT]I cleaned the throttle body with carb cleaner and brush
    2.[FONT=&quot] [/FONT]Cleaned Mass air flow censor with mass air flow cleaner.
    3.[FONT=&quot] [/FONT]Changed air filter
    4.[FONT=&quot] [/FONT]Changed spark plugs
    5.[FONT=&quot] [/FONT]Changed oil (5w30) and oil filter (3.5 Quarts instead of 4 so it won’t be over filled)
    6.[FONT=&quot] [/FONT]Cleaned battery terminals and cable connectors.
    Car ran great on my 50mile test drive went up a good hill then on freeway and some city streets, no more triangle of death.

    Thanks so much for all your help every one

    Paul
    2002 Toyota Prius Aqua Blue Ice
     
  6. tochatihu

    tochatihu Senior Member

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    Good initial outcome. You have developed high-level Prius DIY skills according to that list. I'd still like to hear that the inverter coolant reservoir looks like it's pumping well.

    Ws there a lot of soot visible on the throttle butterfly before cleaning? Did you use the spring-loaded thing to rotate it by hand (with Prius off)?
     
  7. slimfrancis

    slimfrancis Member

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    yepp! i was getting a 3191 code along w/ warning lights as well on my 2001. car would start and turn off after a few seconds. i read this post and bought a $7 bottle of maf cleaner at autozone. i took off the mass air flow sensor, sprayed it good with the cleaner, screwed maf sensor back on and BINGO, no warning lights, car runs and drives with no problem now.