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2 defroster lines not working...

Discussion in 'Gen 2 Prius Main Forum' started by theclarinetguy32, Oct 29, 2010.

  1. theclarinetguy32

    theclarinetguy32 Member

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    Location:
    Fox Valley, WI
    Vehicle:
    2007 Prius
    Model:
    Three
    Hello all,
    This morning we had a bit of a light frost on the cars and when I turned on the rear defroster I noticed that 2 different lines were not doing anything/heating. To my knowledge I can't think of anything which may have nicked the line. But then if two different lines are both not working I would think there might be an issue with the edge contacts. Just guessing here, haven't tried to troubleshoot anything yet.

    I just passed my warranty period so preferrably whatever needs to be done is possible on my own.

    On a side note, the lower rear mini window does have a nick in one of the defroster lines. Long story but whats done is done. I haven't a clue what could be used to fix this but if it's within a reasonable grasp as possible on my own, please tell!!!

    Thanks!
    Jeremy
     
    #1 theclarinetguy32, Oct 29, 2010
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    It is possible to purchase conductive paint which is used to repair nicks in the defroster line. You would apply masking tape above and below the nick to protect the glass, then apply the paint over the nick.

    To troubleshoot the other defroster lines where you don't know the nick's location, you would use a voltmeter. One lead is connected to one end. The other lead starts at the other end. You should measure ~12V when the defroster is turned on.

    If the line was working properly then the voltage should decrease in a linear fashion as you move towards the first end. However, since you have a break in the line, the voltage will remain at 12V until you reach the nick, at which point the voltage will abruptly drop to zero.

    Wrap the voltmeter probe in aluminum foil to reduce the chance of making new nicks in the defroster line.
     
    #2 Patrick Wong, Oct 29, 2010
  3. theclarinetguy32

    theclarinetguy32 Member

    Joined:
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    Location:
    Fox Valley, WI
    Vehicle:
    2007 Prius
    Model:
    Three
    Thanks Patrick!
    I was able to find a repair kit that seems to be offered at most auto stores.
    I am wondering though, if I don't find any nicks on the main rear window lines, is there a recommended procedure for repairing where the line intersects the side strip? (in case that is the problem)

    I'm guessing the main strips on either side of the window are a bit more sturdy considering they feed all the individual lines, but still are a conductive material of some sort.
     
    #3 theclarinetguy32, Oct 29, 2010
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
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    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    I would use the conductive paint for that repair, as well.
     
    #4 Patrick Wong, Oct 29, 2010
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