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04 Prius warning lights lit up like xmas!

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by kc5swi, Jul 27, 2010.

  1. kc5swi

    kc5swi New Member

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    06 Prius warning lights lit up like xmas!

    Hey Guys! My 2006 Prius has 79k miles on it with no issues prior to this. It hasnt been back to the dealer since it left new. Yesterday, after sitting in the car 45 minutes at the airport waiting for luggage, I started the car and got multiple warning lights. The car has been driven daily (20+miles) and was not parked at the airport long term. The red triangle, the maint req, the check eng(symbol) and the airbag light are now on. On the display, the car with the red explanation point is on.

    I drove it home 12 miles, seemed to run fine. Read here and went and checked the 12v battery after it had been parked a day. 12.4 volts with the interior lights on at the battery. I did the diagnostic check and under lan monitor, EMU=chek, and DSO=chek. I cleared the codes and restarted and the lights are still on. Back into diastic mode, no codes shown, I checked voltage under vehicle signal, it is 13.9.

    Any ideas what could be wrong? Should I replace the 12v battery as its 4 years old to start or just take to the dealer. I dont trust dealers much so any input is appreciated! I had not run the radio or left it in assecery mode, in fact I started the car every 15 min to run the AC to cool off for about 5 minutes at a time.
     
    #1 kc5swi, Jul 27, 2010
  2. firepa63

    firepa63 Former Prius Owner

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    Replace the 12v battery.
     
    #2 firepa63, Jul 27, 2010
  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Re: 06 Prius warning lights lit up like xmas!

    MAINT REQD is just telling you that your car needs an engine oil and oil filter change.

    How did you clear the codes? Did you disconnect the 12V battery negative terminal?

    If yes, and all of the warning lights that you mentioned are still on, then I think you should visit a dealer service dept so that the DTC can be read.

    If no, then try disconnecting the 12V battery negative terminal, wait 5 minutes, reconnect, and see if the same warning lights remain.

    It's not obvious that the 12V battery needs to be replaced at this time, but you can do so if you want to rule that out as an issue.

    If you had to wait in the car for an extended period, I think it would have been better if you left the car READY and then set the cabin temp to an appropriate level, rather than start the car every 15 minutes to run the AC for 5 minutes at a time.
     
    #3 Patrick Wong, Jul 27, 2010
  4. kc5swi

    kc5swi New Member

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    Re: 06 Prius warning lights lit up like xmas!

    I charged the battery and it came up to 12.9 v pretty fast. I will reconnect and see if the lights are still on. I tried to read the codes but the scanner couldnt do it. Any other ideas?
     
    #4 kc5swi, Jul 27, 2010
  5. Patrick Wong

    Patrick Wong DIY Enthusiast

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    The fact that the battery went from 12.4V to 12.9V "pretty fast" (what does that mean, 2 hours or less?) would imply that it doesn't have much capacity. The faster the battery will charge, the less capacity it has.

    I'm assuming that your 12V battery is original equipment, thus is 4 years old. It would probably be a good idea to replace the battery now.

    After you've replaced the battery, if the warning lights remain, then you'll need to have your local dealer service dept retrieve the DTC and provide a diagnosis.
     
    #5 Patrick Wong, Jul 27, 2010
  6. richard schumacher

    richard schumacher shortbus driver

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    You drained (and, apparently, killed) the 12V battery by repeatedly turning the car ON and then shutting it OFF again. It takes a good 20 minutes ON to recharge the 12V battery. As Patrick wrote, if you're sitting in the car just leave it ON, in Park (NOT Neutral!) and with the parking brake set, and let it manage its own batteries the way it was designed to do.
     
    #6 richard schumacher, Jul 31, 2010
  7. kc5swi

    kc5swi New Member

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    Guys, I replaced the 12v battery and all is well now. No further issues. Before I changed it even the AC quit driving down the road! Its all good now.
     
    #7 kc5swi, Aug 1, 2010
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