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Xmas Lights situation: Slip+ Brake Trouble + yellow Electric Park + ABS with BLINKING Cruise Control

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by andreimontreal, Dec 13, 2023.

  1. andreimontreal

    andreimontreal Active Member

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    I had the 4 lights come on and the cruise control won't work anymore now - it blinks when I try to set an acceleration. At first the 4 lights would come on, then go away after a few seconds, then they did it for longer. And now they're on permanently. The brake fluid is at the minimum - I suspect it cold be that.

    Anybody else got a clue? Going to check for codes with Techstream.

    Here's a shot of the dashboard:


     
    #1 andreimontreal, Dec 13, 2023
    Last edited: Dec 13, 2023
  2. Tombukt2

    Tombukt2 Senior Member

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    I imagine the car thinks it can't stop because of the brake problem so it won't allow you to set the cruise control seems logical actually I can't wait to see the codes
     
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  3. andreimontreal

    andreimontreal Active Member

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    Yes, indeed it crossed my mind. As for the codes, I'm waiting for motivation to get out of bed (after working late last night) :sleep: will do.
     
  4. bisco

    bisco cookie crumbler

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    has the brake booster buzzing been getting more common?
     
  5. andreimontreal

    andreimontreal Active Member

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    Not from what I remember. I know what you're talking about. I took my car back to Toyota about 4 years ago and apparently they replaced the brake booster assembly (whatever it's called) under the recall program. I was thinking it could be it. But it behaves quite normally. I think I lost regen - because fuel efficiency is worse.
     
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  6. bisco

    bisco cookie crumbler

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    i wonder where the brake fluid went, have you been keeping an eye on it?
     
  7. Tombukt2

    Tombukt2 Senior Member

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    Usually you can look at your screen if you're in the right screen and see when you step on the brake that regen is working You should also feel it when you take your foot off the gas and pull the lever into the b mode. I'm not sure running low on brake fluid would kill your regen But it sure might kill the hydraulic part of your brake clamping and that would not be a thing.
     
  8. bisco

    bisco cookie crumbler

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    Yeah, just slip it into neutral
     
  9. andreimontreal

    andreimontreal Active Member

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    Not sure if it went anywhere. I might've left it like that since the last time I bled a brake. I topped it off anyway and will see if there's an issue with losing fluid. And I think I was wrong about regen. The car drives pretty much normally - those dash lights come and go. At times the ABS system clicks when I depress the brake and the slip sign pulsates.

    I managed to read the codes ( Techstream screenshot ).

    C1239 - Foreign Object is Attached on Tip of Rear Speed Sensor LH
    C1467 - Rear Speed Sensor LH Circuit

    It appears there's dirt over my rear-left speed sensor? I have to take it out of the fork and clean it I suppose? It rather matches the ABS/slip kicking in behavior.
     
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  10. bisco

    bisco cookie crumbler

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  11. ChapmanF

    ChapmanF Senior Member

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    The rear sensor is integral with the hub/bearing assembly. The foreign object may be rust or particles inside there from bearing wear.
     
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  12. Tombukt2

    Tombukt2 Senior Member

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    Yeah you won't be removing any rear sensors you'll just be undoing a plug The rear is sealed I have two laying on the ground here ready to go and whichever of these cars is going to go first I just plug up unlike the front which you can pull out with a 10 mm bolt removal and clean the tip of those they can get crap on them The rears the crap you can't clean off.
     
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  13. andreimontreal

    andreimontreal Active Member

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    Thanks guys. I did some research and I came to the same conclusion and I was about to ask about it.

    Seems like I either have to change the whole bearing assembly or the harness. I saw a mechanic explain how to check the harness first.

    If I drive with it like this for a while, there's no issue I suppose?
     
  14. rjparker

    rjparker Tu Humilde Sirviente

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    Foreign object code is not the harness. Bearing time.