Help! Dashboard lit up after cat replacement

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by PerezPrius, Dec 20, 2025 at 2:38 PM.

  1. PerezPrius

    PerezPrius New Member

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    3146306852184853193.jpeg 7888010798158439409.jpeg IMG_6898.jpeg 3146306852184853193.jpeg 7888010798158439409.jpeg IMG_6898.jpeg I have a Gen 3 (2014) that got the cat stolen in NYC. The mechanic shop quoted $1500 for aftermarket install. The car had no problems when we dropped it off, just missing cat and O2 sensor.

    When we went to pick it up the mechanic said the car has computer problems also and we saw the dash was lit up. He say his upscale computer isn’t resetting it.

    I attached a pic but It’s ABS light, brake light, traction control, and some others. The codes are C1203, C1232, C1336, C1345.

    After driving a couple days as he suggested the codes didn’t go away so he opened the steering wheel and say we may need to replace the clock spring and Steering Angle sensor.

    I asked him if maybe the tech working on the Catalytic converter messed something up but he says he checked everything. This shop did a bunch of work on another car of mine recently and there wasn’t an issue after ward so I’m confused.

    Anyone have a clue what might cause this? I saw there’s a bobby pin method to reset the lights but I haven’t tried it yet.
    Any input appreciated!!!
     
  2. PriusCamper

    PriusCamper Senior Member

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    Ask the mechanic who worked on the car about the condition of the wires that were cut/torn from O2 sensor when Cat was stolen? Those loose wires can short out one of the computer's vehicles if they touch metal and because it had not failed when you dropped it off it means that swapping out that ECU to fix the problem might be covered by them partially or fully. Of course you don't have an ECU failure code so...
     
  3. PriusCamper

    PriusCamper Senior Member

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  4. Tombukt2

    Tombukt2 Senior Member

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    Well he needs clear out info for brake parts it looks like according to some scan pics . I would imagine till that happens you locked out of brakes as far as the finished repair. So it's like mostly completed ? Two brake parts in this model they both talk to car with wires or such . Only 1 piece replaced?
     
  5. Brian1954

    Brian1954 Senior Member

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    Tom, read the title of the thread. The cat was replaced. No brake parts were replaced.
     
    #5 Brian1954, Dec 21, 2025 at 9:34 AM
    Last edited: Dec 21, 2025 at 10:08 AM
  6. Tombukt2

    Tombukt2 Senior Member

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    I did . But you have brake codes now . Ripping out the 02 wires is a stretch to get to brake codes .do you now probably have issue with brakes on a gen3 .unless the cat steal involved ripping out a wheel sensor wire . But that 1365 or 4 won't come for that . Sooóo I didn't lok at other codes . On that list . Those 2 usually all I need . Unless 12V isn't but that would've been mentioned. Charge 12V secure all connections delete codes . What returns 1365 or 4 . And welp .
     
  7. rjparker

    rjparker Tu Humilde Sirviente

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    I have seen guys use an aftermarket o2 sensor and get the sensor wiring wrong since the colors do not match. I made a drawing to spell it out for them.

    Also the Toyota wiring diagrams don't show the colors of the 4 wires built into the sensor extending to the factory wiring harness. This is where they get cut, eg the sensor wires, not the factory harness. The aftermarket sensor comes with a cross reference to the 4 wires on the factory sensor.
     
    #7 rjparker, Dec 21, 2025 at 11:58 AM
    Last edited: Dec 21, 2025 at 12:42 PM
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  8. Tombukt2

    Tombukt2 Senior Member

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    Can wiring up the O2 sensor wrong force brakes to code ?