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2012 shutting down while driving

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by rossrosseland, Aug 28, 2019.

  1. rossrosseland

    rossrosseland Junior Member

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    Im trying to help my buddy fix his car. Ive searched all over but cant find an answer. His 2012 regular prius will shut off on the freeway. All the warning lights come on. He pulls over, stops, starts it, and goes again.

    The local dealer doesnt know what to do. My scantool doesnt show any battery or temp issues.

    Does anyone know a way to troubleshoot this? Ive heard maybe the ignition switch, inverter/connection solder joints, or something in the wiring harness could be making intermittent contact.

    Thx in advance
     
  2. bisco

    bisco cookie crumbler

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    You need tech stream

    Check for movement in the inverter fluid reservoir
     
  3. rossrosseland

    rossrosseland Junior Member

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    Well, the car died more now. I have the torque app and an obdii bluetooth connector. Last week it was driving fine. The dealer had fixed a bad pin on a harness connector. The inverter pump was spinning at 4800 rpm (if i remember right) and inverter temps were 160ish. The hybrid battery voltages were good.

    He was driving it for a week and it seemed ok. No random shutdowns occurred. The all of a sudden it died again. But this time it wouldnt start. He towed it. The dealer said there was getting no connectivity to the data stream and he needed a new harness for $6500.

    The car goes to ready with all warning lights on. When you try to put it in gear, it goes to neutral and the triangle of death starts blinking. Inverter pump wont run. Engine wont come on.

    Any thoughts? TIA.
     
  4. bisco

    bisco cookie crumbler

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  5. Patrick Wong

    Patrick Wong DIY Enthusiast

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    When the dealer quotes a price of $6,500 to replace the wiring harness, basically the message is that you should tow the car to a salvage yard and turn over the fobs and title.

    Let's start with the inverter pump not running. Check the 30A IGCT fuse and the 10A IGCT3 fuse. Measure voltage from the fuse socket to body ground. You should be able to measure 12VDC from one side of the fuse socket.

    If you get voltage at the 30A IFCT fuse socket but not at the 10A IGCT3 fuse socket when the car is IG-ON, then the IGCT relay is not closing. Remove that relay. Locate the relay coil terminals which should have ~100 ohms resistance. Apply 12VDC to the coil terminals. Measure resistance across the switched terminals which should be close to zero ohms.
     
  6. rossrosseland

    rossrosseland Junior Member

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    Thx Patrick. We'll check that. I think there's issues deeper than just the inverter pump as the car won't go into gear (it just goes into neutral and the engine won't ever kick on even with AC turned on or the throttle applied) and the dealership couldnt connect to the computer. We are thinking a computer or harness might have a bad connection. Is there a common problem that would cause those issues?
     
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I recognize your car has problems beyond the inverter pump. The reason I suggested you focus on that is because it is a relatively simple subsystem. If you can figure that out, you may find that the solution helps to resolve other issues.
     
    rossrosseland and Mendel Leisk like this.
  8. rossrosseland

    rossrosseland Junior Member

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    We disconnected the small battery and now it's running. All warning lights are off.

    Does anyone know anything about the recall for the sudden limp home mode or shutdown problem? This one seems to be doing that. The tech at the dealer said the software needed updated (which they did) but he said the inverter didnt need changed as the code that triggered them to do that wasnt set or stored in the car's obd system.

    Is there a computer or chip (either the main ecm or inside the inverter) we could replace to attempt to solve this issue?
     
  9. bisco

    bisco cookie crumbler

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    running fine? no lights?
     
  10. rossrosseland

    rossrosseland Junior Member

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    Yes, thats what it does. Runs fine, no lights, then it shuts off on the freeway randomly. Warning lights come on. Sometimes they go off when it's restarted; sometimes they stay on. The last time took a disconnect of the battery to get it driving again.
     
  11. bisco

    bisco cookie crumbler

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    did you replace the inverter pump?
     
  12. rossrosseland

    rossrosseland Junior Member

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    No. Wouldn't the inverter temp be high if the pump failed? And I don't think the pump would fail intermittently, would it?
     
    #12 rossrosseland, Sep 9, 2019
    Last edited: Sep 10, 2019
  13. bisco

    bisco cookie crumbler

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    idk. is there fluid moment in the reservoir?
     
  14. rossrosseland

    rossrosseland Junior Member

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    Yes, except this last time when the car shut down and he had to get it towed. The dealer messed with it. They couldn't get it to communicate with the diagnoatic equipment. The engine wouldn't come on and the car wouldn't go ready or go into gear. We had to disconnect the battery and now all the warning lights are off and everything is working, including the inverter coolant pump.
     
  15. Chuba

    Chuba Junior Member

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    The problem is your engine water pump or inverter coolant pump has gone bad. 1st check the fuse. If not blown change pump