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2008 Prius - Engine Light Check/Red Exclamation Mark - 12V Battery OK

Discussion in 'Gen 2 Prius Main Forum' started by SRK444, Jun 10, 2013.

  1. SRK444

    SRK444 New Member

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    Austin, Texas
    Vehicle:
    2008 Prius
    Model:
    N/A
    Hello All:
    I've been using my prius 2008 very smoothly till today. It was 100F+ in Austin and very hot. The car, suddenly lit up all the warning lights: Engine, Red Exclamation, Hybrid, and brake lights. The brakes kept beeping on both sides. I also heard an engine noise that is quite uncommon for prius. I stopped the car in a parking lot.
    I came back in an hour and tried to start the car. I only saw 2 lights now: Red Exclamation, and Engine check. It might some "click" noise when I started, and after that it was fine. I drove for a while and everything was fine but the 2 warning lights were still on. I tried starting and stopping few times. I did experience the clicks (1-2) and the engine noise. The engine noise lasted 15-30 seconds and then it was back to normal.
    I followed the youtube video to look up the diagnostics (Display pressed + lights on/off 3 times) to check the 12V battery. It read 13.8 V. I recently had an oil change at Toyota dealership less than 500 miles back. So I am baffled at this point. I have about ~60K miles and it's a 2008 model. So if it's a hybrid battery issue, I am covered but I want to see if any experts have any light to shed on this.

    Thanks in advance for your time and help.
     
    #1 SRK444, Jun 10, 2013
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    See if the inverter coolant pump is running: make the Prius READY, open the hood, then look for fluid turbulence within the inverter coolant reservoir. If you do not see turbulence, the pump has failed and that is the root cause of your car's problems.

    If you see turbulence, then your car has another problem.

    The condition of your car's 12V battery is unknown at this time based upon the test you described. Your measurement of 13.8V shows that the DC/DC converter within the inverter is working. That says nothing about the 12V battery condition. What is needed is to determine the battery voltage when the Prius is not READY, ideally after the car has rested unused overnight.
     
    #2 Patrick Wong, Jun 10, 2013
    cwerdna likes this.
  3. SRK444

    SRK444 New Member

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    Austin, Texas
    Vehicle:
    2008 Prius
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    N/A
    Thank you Patrick.
    I checked the battery this morning and it read 13.9V on the diagnostic window. Can I now assume that the 12V battery is fine?
    Also, I checked the coolant reservoir. I heard a huge engine noise, so it was hard to tell if there was turbulence in the fluid. I did see the fluid move but when I turned it on and off few times, the engine noise went away but I didn't see any visible turbulence. Does that mean the pump has failed?
    We're thinking about calling Toyota dealership this morning. Is there something else that can be done or is calling them the best way forward?
    Thanks for your help.
     
    #3 SRK444, Jun 11, 2013
  4. SteveLee

    SteveLee Active Member

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    You're still checking the battery in the READY mode, while it is being charged. It has to be checked while not in READY mode, so it is not being charged. Go back and re-read the instructions, without the brake depressed. You need all three readings.
     
    #4 SteveLee, Jun 11, 2013
  5. Riaz

    Riaz Junior Member

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    2006 Prius
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    II
    Hi SRK444,

    To do an effective test of the 12v battery you need to test it with a DC voltmeter with the car completely off or in accessory mode (single press of power button without depressing brakes) and with some electrical load on eg the headlights. The measured voltage with the headlights on should be higher than 12v and should not be dropping quickly for a good battery.

    However, based on your indication of a strange engine sound I doubt the 12v battery is the problem. I have driven my 06 Prius with a near flat 12v battery that was bearly able to get the car into ready in the morning and the car drove fine without any warnings...but every case is unique so you can't rule it out completely.

    I'd take it to the shop to have it checked out...it's possible that the engine is overheating and the strange sound you're hearing is the radiator fan kicking in but that's just speculation...you need to get the codes read at a shop for a proper diagnosis. Hope it's just a minor problem...good luck!
     
    #5 Riaz, Jun 11, 2013
  6. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Contacting your dealership is probably the best action plan at this time, since it sounds like you need a new inverter pump. This is covered under a recall program for older 2G Prius, so if your car is not covered just pay the bill and then write to the Toyota Customer Experience Center for a refund.
     
    #6 Patrick Wong, Jun 11, 2013
  7. SRK444

    SRK444 New Member

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    Vehicle:
    2008 Prius
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    All,
    Thank you very much for your efforts to help. So it finally turned out to be the AUX battery, and couple of other things (I have to check the paperwork) that were under recall. They only charged us for the battery which was around $300. I'll post the detailed problem from the paperwork sometime soon. Thank you all again.
     
    #7 SRK444, Jun 12, 2013
  8. bisco

    bisco cookie crumbler

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    glad you're sorted out, all the best!(y)
     
    #8 bisco, Jun 12, 2013
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