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Pre-collision system malfunction

Discussion in 'Gen 4 Prius Main Forum' started by shadow4478, Nov 16, 2022.

  1. shadow4478

    shadow4478 Member

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    2017 Prius
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    Today out of nowhere message displayed “pre-collision system malfunction visit your dealer”
    Cruise controller raider works Lene assist works any information on this?
     
  2. shadow4478

    shadow4478 Member

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    The windshield was changed about two months ago. They did say it may need to be recalibrated, not sure if that has to do with anything as the lane sway assist works
     
  3. jdenenberg

    jdenenberg EE Professor

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    Shadow,

    The radar is behind the Toyota front emblem. If it gets dirty, the safety systems can shut down. Take a wet rag and clean it. Hopefully that will correct the issue.

    JeffD
     
  4. shadow4478

    shadow4478 Member

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    No, it’s clean washed off same thing
     
  5. Elektroingenieur

    Elektroingenieur Senior Member

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    To find out why the message appeared, you (or a dealer or independent shop) need to retrieve the diagnostic trouble codes (DTCs) stored in the driving support ECU assembly, and then review the related information in the Repair Manual (more info).

    This requires a Toyota Techstream diagnostic system or true equivalent; inexpensive OBD II code readers made for engine and emissions diagnosis aren’t programmed to communicate with the driving support ECU.
     
  6. AzWxGuy

    AzWxGuy Weather Guy

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    A camera recalibration is definitely required after windshield replacement. Otherwise, have you disconnected your 12V battery lately? There is an ECU requiring a reinitialization procedure. The non-operational fault is mentioned in the user manual on page 301, and the initialization procedure is on page 383. These procedures may be on different pages in your manual. My manual is Toyota 2021 Prius Owner's Manual (OM47E09U).
     
  7. MikeV

    MikeV Junior Member

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    Did you ever figure this out?

    Having exact problem as yours
     
  8. shadow4478

    shadow4478 Member

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    For me it was the camera, they nicked a clip while replacing the windshield, they tried to tape it with double sided tap but didn’t work, then they ordered a new clip and it worked without issues.
     
  9. MikeV

    MikeV Junior Member

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    was it covered under warrant and why did the lda LDA still work