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Brake light switch not engaging

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Liquidgsr, Feb 25, 2022.

  1. Liquidgsr

    Liquidgsr Junior Member

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    I have a 2012 prius and I had removed the brake actuator from the pedal. When I went back and installed it my pedal isn't hitting the brake light switch anymore. There is about a 2 finger gap between the metal part that is suppose to push on the sensor to turn the brake lights off. Am I missing something? The picture makes it look like its coming in contact but it's not. There is a two finger gap. Am missing a part? Or did I install something wrong?
     

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  2. OptimusPriustus

    OptimusPriustus Active Member

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    It should be the other way round. Brake light go on when switch is pushed. You have not tried whether it works or not?
     
  3. ChapmanF

    ChapmanF Senior Member

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    OP has it right. The brake lights turn off when the switch is pushed (by the pedal coming to the top of its travel).

    When you push the pedal, it releases the brake switch, and the brake lights come on.

    The photo makes me wonder if the master cylinder got properly seated all the way back up against the firewall.
     
  4. Mike72903

    Mike72903 Junior Member

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    Realize this is an old posting but I would like to know how to remove that brake light switch. I have access to it from under the dash. Being plastic I don’t want to break it trying to figure it out. Looks like that brown “wingnut” looking thing may unscrew? Also can it be adjusted without removing it. The bracket it mounts through got bent back in the process of an ignorant and careless newbie (me) replacing the brake actuator. No way that I can figure out to bend it back into position. Just not enough room up there. If I could remove the switch there would be enough room to get vice grips on the bracket. Or if I can just adjust the switch so it operates without removing would be great.
     
    #4 Mike72903, Oct 25, 2023
    Last edited: Oct 25, 2023
  5. ChapmanF

    ChapmanF Senior Member

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    Not sure if it's easier to turn the brown thing, or unplug the switch wires and turn the switch.

    I think it's essentially a threaded nut, but with a one-way 'zip' feature to make installing the switch faster. Haven't had to deal up close with it though.
     
  6. Mike72903

    Mike72903 Junior Member

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    FYI
    Okay, I manned up and dove back under the dash to try again. It turns out (1) that brown nut does NOT turn. Don’t try. (2) one only has to grab the green switch tightly and twist it about 20 degrees and it become loose to move in or out. Once located appropriately twist it back the other way and it locks itself in. No need to detach the wire connector. Simple. Now I know.
     
  7. ChapmanF

    ChapmanF Senior Member

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