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How can you tell the difference between a failed inverter and a failed pump?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Arredla, Sep 30, 2017.

  1. Arredla

    Arredla New Member

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    Hey guys, I've seen a lot of really good information on here about the eternally failing inverter coolant pumps that seem to screw things up for many of us. I started having that problem a few days ago and was set to bleed my coolant and possibly swap a pump out this weekend.

    Then when I was driving to the store, the (!) light came on and this time the engine shut off. It was as though I had run out of gas. I turned the car off and on again, but it only made it about 250 feet before shutting off again. I'm pretty sure the pump was bad, does it sound like I didn't make it in time and now I need a new inverter too? Kind of hoping that's not the case particularly since I was about one hour away from solving the problem. Figured I'd come to you guys for your opinions to see if I'm really sunk here.
     
  2. SFO

    SFO Senior Member

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    A failed pump won't vibrate, try touching it.

    A failed pump won't produce coolant turbulence in the reservoir.
     
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  3. fotomoto

    fotomoto Senior Member

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    If after a good cool down period and the car begins to operate again, the inverter should be OK.
     
  4. Arredla

    Arredla New Member

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    Okay, you think the car just wouldn't start at all if the inverter's dead? I'll check it out. Thanks man, will report back.
     
  5. exstudent

    exstudent Senior Member

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    1. Just make the car IG-ON (don't step on the brake, press Power twice) or READY (depress brake, press Power button once).
    2. With hood open and propped, open inverter coolant bottle. Do you see fluid movement? It would look like a slow, gentle flowing stream. Many people say turbulence, which I feel to be a mischaracterization; describing fluid movement as turbulent = white water rapid to me.
    3. If the environment is quiet enough, you should hear the inverter pump, which sounds like an aquarium air pump.
    4. You should be ale to feel a gentle vibration on the plastic inverter overflow container.

    You most likley have a bad inverter pump that needs to be replaced.
     
  6. edthefox5

    edthefox5 Senior Member

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    If the inverter failed it would throw a lot of lights primarily the red triangle master caution light.
    The car would not ready with a failed inverter. It would not do much except throw a lot of codes.

    Stop guessing and Harvest the codes including there subset codes and post back here. Obd code reader must be hybrid capable.
     
  7. Arredla

    Arredla New Member

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    Huh, well oddly enough I just got a call from the dealer and they said there's no lights on and the car is driving fine. I'm gonna take it home and change the coolant pump myself since like I said I'm pretty sure that's been bad all along. Funny enough when it died in the first place every light came on and I couldn't even get it to turn off, I'd hold the power button but it would take 30 seconds or so to shut off, kept having to put the hazards on and stall out in the middle of an intersection. But then I guess it got some time to think about what it did and it's starting up fine now. Sounds like a new pump is in order, I'll let you guys know how it goes. Thanks for all the tips, glad the whole thing didn't blow up.
     
  8. 05PreeUs

    05PreeUs Senior Member

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    STEALership!

    If any warning lights come on, a code was logged... somewhere, they need to look harder so you do not get stranded.
     
  9. Arredla

    Arredla New Member

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    Even stranger, they didn't charge me a dime. I was shocked, maybe the battery died and erased all the codes. It is driving fine now though, so I'm going to order a coolant pump off eBay and try to swap it out this week.
     
  10. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Also make sure the 12V battery is in good condition and replace it if in any doubt. Start by fully charging the battery.

    It appears that the voltage dropped sufficiently so that the ECUs lost logged DTC.