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AC failure, HEAT failure

Discussion in 'Gen 2 Prius Main Forum' started by 4plasticfish, Nov 23, 2010.

  1. 4plasticfish

    4plasticfish New Member

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    I am new to this forum so sorry if this is posted somewhere but I cant find it. I have a 2005 Prius. Today, after filling up with gas, the heat and AC along with front defroster stopped working. All the displays work, controls all work, but nothing happens when it says it is on. The fan does not blow at all on any setting, hot or cold. I appreciate any and all help.

    Also, how do you reset the computer on a Prius? Can you disconnect the 12 volt battery, or use an Can OBD scanner to reset?

    My 12 volt battery is original by the way.
     
    #1 4plasticfish, Nov 23, 2010
  2. GrumpyCabbie

    GrumpyCabbie Senior Member

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    I think you half know the answer. I'm sure many on here will want to know what fault codes the car has thrown, but the 12v battery is a weak spot on the Prius, apparantly with an average life of about 4 - 5 years.

    I suppose it's upto you whether you fit a new 12v and see if that solves your problems as it might be prudent to change it at 5 years old anyhow (if it hasn't faulted yet, it soon will). However, if the problem lies somewhere else, you don't want to be throwing money at a car that might have a more serious problem somewhere else.
     
    #2 GrumpyCabbie, Nov 23, 2010
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  3. fotomoto

    fotomoto Senior Member

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    Then stop getting gas!*

    +1 on checking the battery first thing.




    *apologies to Henny Youngman
     
    #3 fotomoto, Nov 23, 2010
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    1. It is likely that the blower motor needs to be replaced.

    2. Prius has multiple ECUs. Most of them will reset if you disconnect the 12V battery negative terminal. A couple (SRS and skid control) have a trickier process that involves using a jumper on the OBD-II socket.
     
    #4 Patrick Wong, Nov 23, 2010
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  5. Rae Vynn

    Rae Vynn Artist In Residence

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    Could it be a fuse? :huh:
     
    #5 Rae Vynn, Nov 23, 2010
  6. 4plasticfish

    4plasticfish New Member

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    OK, a little more info, so the blower has come on a couple of times the past two days. Most of the time it does nothing even though the heat is on. All of the controls and MFD screen settings appear to work as usual. It does not blow on front defrost, heat, AC floor or panel settings.

    I checked the 12v battery with the MFD signal check and it seems ok at 12.1 volts unloaded and 11.8 with a small load.

    Any suggestions? Anyone have a similar problem that they resolved?

    I just know if I go to the dealer I will be buying a new blower and the install for that looks pretty labor intensive. I wonder what that would cost?
     
    #6 4plasticfish, Nov 26, 2010
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

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    1. You need a new blower motor. I recall one or two posts that explain what is involved to replace it. My guess is that your dealer will charge you ~$500 to replace it.

    2. I suggest that you buy a new 12V battery soon since your area has fairly cold winters and it appears that your existing battery is near end-of-life.
     
    #7 Patrick Wong, Nov 27, 2010
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