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Fault Code C1391-ABS/Traction/Brake Lights on-Expensive repair!

Discussion in 'Gen 3 Prius Technical Discussion' started by Chewus, Jan 28, 2021.

  1. Chewus

    Chewus Junior Member

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    Location:
    Seattle
    Vehicle:
    2010 Prius
    Model:
    ----USA----
    After lights came on I took my 2010 Prius to the local Toyota dealer so they could pull the fault code(s). They called me last night before closing and emailed me the fault code the technician found, C1391. Based on code dealer says I need Brake Boost/Master Cyl ($1,018) replaced as well as Brake Booster Pump ($692) and the labor took total estimate to $3500+. I called Toyota Customer Assist Center to see if they could offer any relief as car is like 5-6 months over 10 years old but only has 81,000 miles on it. Toyota said they cannot do anything for me. I will now look for best prices on the two parts and install them myself. Has anyone got any recommendations as to where I can find out instructions on how to do the removal/install? I have never had to work on this car as up until now its been problem free but from what I read this repair may require computer/ software. Any guidance would be greatly appreciated. Thanks!
     
    #1 Chewus, Jan 28, 2021
  2. Elektroingenieur

    Elektroingenieur Senior Member

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    Vehicle:
    2016 Prius
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    Three Touring
    See the Repair Manual (more info) and, as an outline of how to fix this specific problem, service bulletin T-SB-0079-18 Rev1, “ABS Brake Warning Light On” (PDF), November 21, 2018. (The hyperlinks in the bulletin don’t work since it’s on NHTSA’s server, not Toyota’s.)
    You’ll need a Toyota Techstream diagnostic system to bleed the air from the brake system. If you’re following the service bulletin procedure, you’ll also use the Techstream system to check the calibration IDs (firmware versions) of the skid control ECU, and if updates are necessary, to install them.
     
    #2 Elektroingenieur, Jan 28, 2021
    PriusCamper likes this.
  3. Chewus

    Chewus Junior Member

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    Vehicle:
    2010 Prius
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    ----USA----
    Elektroingenieur-thanks for the tips I'll have a look at that TSB tomorrow.
     
    #3 Chewus, Jan 29, 2021
  4. douglasjre

    douglasjre Senior Member

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    Vehicle:
    2010 Prius
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    ----USA----
    Care to share your password for TIS?
     
    #4 douglasjre, Jan 29, 2021
  5. ChapmanF

    ChapmanF Senior Member

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    IV
    I think I remember expressly agreeing not to when I signed up. Elektroingenieur probably did the same.

    But Elektroingenieur did put in the effort of constructing an entire wiki page documenting different ways of getting access to the docco, be it through TIS or local libraries providing free access, etc.
     
    #5 ChapmanF, Jan 29, 2021
  6. douglasjre

    douglasjre Senior Member

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    ----USA----
    C1390: fuel pump seized. .2ohm but no rotation.
     
    #6 douglasjre, Feb 2, 2021
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