Automatic parking brake activation sound

Discussion in 'Gen 5 Prius Main Forum' started by mannymendez25, Oct 4, 2025 at 10:41 AM.

  1. mannymendez25

    mannymendez25 Member

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    I have the automatic parking brake feature active when turning off the car, however, it seems to be annoyingly loud. When I park my car, get out of the car, lock the car, get the mail, bring in the garbage cans and all of a sudden, after all that time, I hear what seems like the parking brake activating. Is this sound normal?
     
  2. Mendel Leisk

    Mendel Leisk MMX GEN III

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    Might be the evap system doing something, that has always been thus.

    Assuming you’re parked on level ground, right after getting out try giving the car a push, if it won’t budge a foot or so, the parking brake is set.
     
  3. ChapmanF

    ChapmanF Senior Member

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    Can you record the sound?

    The parking brake, I would expect to get applied right as you park and turn the car off, not some time later.

    The fuel evap system self-test probably happens way later—not sure about gen 5, but in gen 3 it's five hours after turning the car off (sometimes longer depending on temperatures). It sounds sort of like a small fan running for several minutes near the back of the car. I'm guessing that's not what you're describing.

    Gen 3 has a brake system self-test that takes place 90 seconds after turning the car off. Sounds kind of like click-squish-click-squish-clickclick. Sometimes also with the sound of the pump running. Gen 5 might have something like that too, though the brakes changed a lot from gen 3 to 5, so I'm not sure what details carry across.
     
  4. mannymendez25

    mannymendez25 Member

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    I believe I can disable the automatic parking brake feature. I live in Florida and the only hills we have here are parking lot ramps. LOL. I really don't need it. I will disable and see if the noise continues.
     
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  5. bisco

    bisco cookie crumbler

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    mine sounds like a noisy zipper
     
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  6. ChapmanF

    ChapmanF Senior Member

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    A noisy zipper zipping when you park / turn the car off, right, not some get the mail and bring in the garbage cans later?
     
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  7. bisco

    bisco cookie crumbler

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    just when i press park. car can still be ready. and it only activates on a slope over so many degrees, i'm not sure how many