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Power loss & hybrid warning light

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by 8WheelsGood, Apr 8, 2008.

  1. 8WheelsGood

    8WheelsGood New Member

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    We have a lovely Prius which I do not want to drive on the highway anymore. Perhaps someone can help me regain my faith!

    Our car is currently in the dealer's shop because (for the 3rd time in it's life) it lost power suddenly. Everything was normal while driving in the city at 30mph and then suddenly no power was transmitted to the wheels. We heard the gas engine, but had neither gas nor battery power and the hybrid warning screen appeared. (No special codes.)

    After safely getting off the road we were towed to our repair shop where they could find no codes, could not replicate the problem and said everything is fine.

    The kicker? A similar thing happened 5 months ago (but at freeway speeds.) That time we DID have battery power so were able to limp off the highway. That time the same shop blamed the (dead) 12volt battery and said they could not access relevant codes because the battery had died. After testing, they proclaimed everything fine.

    I've had good luck with this shop in the past - they performed a warranty repair October of 05 when we lost gas power the first time. Nice to deal with and seemingly competent folks. We had a faulty fuel sensor which lead to the engine shutting down. The engine control module was also replaced. (I'm thinking this was per the TSB EG011-03 bulletin, but am unsure.)

    Good thing we all like riding bikes.
     
  2. AngelFish

    AngelFish New Member

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    my red 04 prius had that sensor fail on it twice. both times they repaired it under warranty. My husband's white 04 - similar mileage, no problems.

    We replaced the red (totalled) with an 08. I am hoping never to see that problem again.
     
  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    What is the odometer reading on your vehicle?

    Is your 12V auxiliary battery the original battery; or was it replaced five months ago after your second problem occurred? If the battery has not been recently replaced, I suggest that you replace it now.

    If your Toyota dealer is not able to retrieve any DTC, they won't be able to do much for you. However, if the check engine light came on or the MFD showed a hybrid vehicle warning icon, then DTC should have been logged.
     
  4. 8WheelsGood

    8WheelsGood New Member

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    We have about 75,000 miles on the car.

    Yes, the battery was replaced 5 months ago.

    Pardon my ignorance; is the MFD the main display? Because yes, we had the evil triangle of excited death. I was _sure_ the shop would find some codes. I will press them again.

    Could this be a simple intermittent connection that sends a bad signal to the computer? Maybe a bad fuse or sensor that just sends garbage?

    I'm a former high-end espresso machine repair person, so I've had my share of mysterious errors in electrical systems. I don't know combustion engines or transmissions from my big toe, though.

    Your insight is welcome!
     
  5. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Since you have 75K miles on the car, it sounds like it is regularly driven. Hopefully the 12V battery, being relatively new, remains in good condition.

    The multifunction display (MFD) is the video display in the center of the dashboard that shows the fuel consumption multi-bar chart and the display with the power flow diagram along with the wheels/tires turning, the battery SOC gauge, etc.

    The master warning light is the red triangle that you saw. That light by itself does not necessarily mean that any DTC (diagnostic trouble codes) were logged.

    However if the check engine light (the amber light that looks like a little engine) or the hybrid vehicle icon in the MFD (the vehicle with the exclamation point) came on, then one or more DTC should have been logged.

    Yes, you might have an intermittent connection. It's hard to know where to look without a DTC to help guide the search.

    Perhaps another dealer might have more success in retrieving the DTC?

    Are any warning lights on now?
     
  6. tochatihu

    tochatihu Senior Member

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    As the subject is a 2001 Prius, I would like the consider the possibility of an accelerator pedal problem. Bob Wilson (a poster here) is now rebuilding these.

    The DTC for this is posted elsewhere, but it does not alway show up when the engine 'loses power".
     
  7. Jan Gartenberg

    Jan Gartenberg New Member

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    Out of nowhere, I was unable to turn on my 2004 Prius last night. All I saw was the yellow check engine light, and that was fading. With repeated pressing of the on button, the dash lit up for a minute or so, but I never saw the "ready" indicator. I jumped the battery and noticed that the hybrid battery was almost full in the display. I was then able to drive the car.

    Today, I was able to turn on the car (but not initially). The red triangle appeared, along with the hybrid vehicle icon (with exclamation point). When I turned the car off, the navigation screen remained lit, and the parking indicator was flashing. Other indicators remained off, but the lights were dim in the car. It seems there is something electrical that is malfunctioning.

    I plan to take it to the dealer tomorrow. The odometer is at 35,000. Any suggestions are certainly welcome.
     
  8. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Hi Jan,

    I think that your problem is simple: you need a new 12V auxiliary battery. The dealer will charge you ~$150 for the battery plus labor time to install.
     
  9. Jan Gartenberg

    Jan Gartenberg New Member

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    Thanks, Patrick-

    I've never replaced that battery. Should I try to install one myself, if you think I can? Or is it best to bring it to the dealer?

    Jan
     
  10. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Hi Jan,

    If you have experience replacing other auto batteries, then the Prius battery replacement should be relatively easy. I suggest you remove the triangle-shaped hatch floor piece located at the right rear of the hatch area to satisfy yourself that you can (or can't) do the job yourself.

    I suggest that you purchase only the correct Toyota battery if you are a novice at this. Please make sure that the battery terminal polarity is correct (when facing the battery with the terminal side closest to you, the positive terminal should be on the left.)
     
  11. Jan Gartenberg

    Jan Gartenberg New Member

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    Patrick-

    Um, I think I'm having the dealer do it...Thanks for your confidence in me. My nursing skills may not cut it here!

    Jan, RN
     
  12. EZW1

    EZW1 Active Member

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    I read that in the '04 to '05 model year there were a few vehicles that experienced the exact same proble you're experiencing. Toyota found the cause and fixed it: a bug in the software. It appears you haven't had that corrected yet. So, I wished I could help you more, but a little research should solve it for you. My guess is you're going to need a new engine control module or a new software flash.
     
  13. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Hi Jan,

    OK. It appears that you have the ability to jump the Prius. That being the case, you may wish to do so again (if the car won't start on its own) then leave the car READY (and in P, or in D if driving) for at least one hour to allow the 12V battery to charge up (not necessary to actually drive the car during this period).

    Then see if the battery holds a charge or not. If not, then a new battery definitely is in order.
     
  14. Jan Gartenberg

    Jan Gartenberg New Member

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    Patrick-

    What do these batteries cost?
     
  15. efusco

    efusco Moderator Emeritus
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    They're around $170 +/- $20 depending upon how bad the dealership wants to screw you over.
     
  16. efusco

    efusco Moderator Emeritus
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  17. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Hobbit has a base model Prius, so the battery shown on his website is smaller than the battery used for vehicles equipped with SE/SS. The latter battery has a black case, not translucent, and is longer. Same height and depth.

    Classic has the same size battery as the base 2G, but with reversed terminal polarity.