Red Square Warning Light

Discussion in 'Gen 5 Prius Main Forum' started by daisy555, Jun 21, 2025 at 6:25 PM.

  1. daisy555

    daisy555 Senior Member

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    This is the second time I’ve had a large red square warning light pop up on my dash screen. It takes up almost the entire left side of the screen. Happened a while ago and I thought it was just a glitch but it just happened again. It says something but it turns off too quickly for me to read it.

    Of course I took my manual out of the car to read about the AC and can’t look it up. Just curious if anyone is familiar with this. Googling was NOT a good idea. : } It just flashes on and then disappears. Thanks
     
  2. Gokhan

    Gokhan Senior Member

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    Probably automatic emergency braking (AEB) or automatic parking braking.
     
  3. daisy555

    daisy555 Senior Member

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    While I’m driving? I forgot to mention that detail.
     
  4. Gokhan

    Gokhan Senior Member

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    Yes, that red “BRAKE!!” warning would only come up while driving.
     
  5. daisy555

    daisy555 Senior Member

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    Well there are no cars in front of me when it happens and no auto breaking occurring.
     
  6. Gokhan

    Gokhan Senior Member

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    It can still get confused or detect something you didn’t see.
     
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  7. Trollbait

    Trollbait It's a D&D thing

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    Or detect something that isn't there.
     
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  8. schja01

    schja01 Senior Member

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    Doesn’t even have to be in front of you. Thinking garage walls, etc.
     
  9. daisy555

    daisy555 Senior Member

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    This happened on a road I travel often. No one in front of me and no one coming towards me. It seems crazy that it would flash such a large warning so quickly that it can’t be read.
     
  10. Trollbait

    Trollbait It's a D&D thing

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    slight curve with a car in a turn lane is where the Subaru has falsely alerted to something in front. The warnings and exceptions in the Toyota manual for these systems is probably longer than the about part.
     
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  11. daisy555

    daisy555 Senior Member

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    Thanks for correcting my spelling. I’m often voice typing and don’t catch every mistake. If that warning is for braking or avoiding a collision the sensors are quite confused.
     
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  12. Gokhan

    Gokhan Senior Member

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    Maybe, maybe not. There are already threads about this such as this:

    Gen5 Prime suffers from phantom brake syndrome. | PriusChat