NEED: Prius LED ECU Delete Harness

Discussion in 'Gen 3 Prius Accessories and Modifications' started by Mark Zurawski, Apr 7, 2026.

  1. Mark Zurawski

    Mark Zurawski New Member

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    Five
    Does anyone know where I could find an LED ECU delete / LED-to-Halogen bypass harnesses for the 2010-2011 Prius Five? Copilot AI says the following PriusChat users have made and/or sold quality solutions on PriusChat: @sfv41901 and @seanw
     
  2. PriusCamper

    PriusCamper Senior Member

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    Are you talking about headlights? If so, I'm pretty sure there's direct swap LED bulbs these days and no need for ECU delete harness. Maybe @Mendel Leisk has more info?

    Also, there's way more accurate AI services than Co-pilot, which is almost bad as the worst, which is Google AI, also known as Gemini.
     
  3. ChapmanF

    ChapmanF Senior Member

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    I was almost about to guess that the OP had a Prius that came with the factory LED-integrated headlight housings, and wants to replace them with the halogen projector housings, and do away with the auto-leveling motors and ECUs and somehow not get the associated trouble codes.
     
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  4. PriusCamper

    PriusCamper Senior Member

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    Now that you mention it... I guess they could be saying that. I didn't consider that someone would be crazy enough to go back in time and go from superior to inferior.
     
  5. ChapmanF

    ChapmanF Senior Member

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    Maybe they took some damage to their original LED-integrated headlight housings, and then priced them.
     
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  6. Mark Zurawski

    Mark Zurawski New Member

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    2011 Prius
    Model:
    Five
    Yes, the factory housings were damaged and I replaced the factory LED system with a lesser-quality LED housings to save a ton of money because I have 4 separate 2010-2013 Prius models in my driveways for my children (to smash-n-crash).

    The 2011 Prius Five in question originally had: #1) A dedicated LED Headlight ECU mounted to the factory housings; #2) A 6-pin triangular control connector, which I spliced around; #3) An auto-leveling motor inside each factory headlight, and #4) A rear height leveling sensor that feeds leveling data to the factory LED Headlight ECU that I removed to install the new aftermarket LED headlight system.

    According to the inferior AI Tool, Copilot, (lol) when any of the above are missing, the car throws three associated codes and displays "Check Headlight System" on the dash and the only known fix is an LED-to-Halogen Conversion Bypass Harness (also called the LED ECU Delete Harness, amongst several other “names”).
     
  7. Mendel Leisk

    Mendel Leisk MMX GEN III

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    Nope. Just the expression causes dismay and bewilderment:
     
  8. Mark Zurawski

    Mark Zurawski New Member

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    Five
    It appears that I may have a solition: CoPilot is stating that I can remove and reattach the factory LED ECU from the factory headlight assembly that will, in theory, eliminate all 3 dash error codes related to the “Check Headlight System” dash message, and I quote:

    “On the 2010-2011 Prius Five LED headlight assembly, the LED ECU is:
    • Mounted on the bottom of the headlight housing
    • A rectangular silver/metal module
    • Attached with 3-4 small screws
    • Connected to the car via the 6-pin triangular connector (the same connector now unplugged in your car
    This ECU is completely separate from the LED driver board inside the housing - it's a removable module.”

    I will now attempt to follow the associated process to reattach only the factory LED ECU to my 2011 Prius V and let y’all know how it goes.

    Thank you all so far & cheers!
     
  9. Mark Zurawski

    Mark Zurawski New Member

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    Five
    …the solution actually involves breaking down the factory headlight assembly innards and removing all (2-3) components that are directly connected via ECU wires inside to the external factory ECU Module, then reattaching the triangle-shaped connector that was unused and unnecessary when installing the new LED replacement Assembly purchased from Amazon.

    The ECU Module and salvaged components from inside the factory assembly would need to be housed in waterproof material and secured inside the engine compartment. This would have restored all headlight-related communications to all of the necessary modules in the car and eliminated the “check Headlight System” error codes and messages (in theory).

    Conclusion & Next Steps: I was able to reconstruct and reuse the damaged factory headlights because they were salvageable as a whole and I kept my headlights factory/stock, which is a big plus.
    …the above solution actually involved tearing down the factory headlight assembly and removing all components directly-connected via ECU wires inside to the external factory ECU Module, then reattaching the triangle-shaped female connector inside the engine compartment that was used for data communications only and became unused when installing the new (lower-quality) LED headlight replacement system purchased from Amazon.

    After removal from the factory assembly, the external ECU Module and internally-salvaged ECU components would need to be secured in a waterproof environment inside of the engine compartment, if I actually chose this route as my final solution.

    However, and although this “solution” should have restored all factory headlight-related ECU communications to all of the necessary modules throughout the car and eliminated the “Check Headlight System” error codes and messages (in theory), I choose a different route.

    Conclusion & My Next Steps: I am able to reconstruct the factory assembly shell and reuse the damaged factory headlights because they were salvageable as a whole without tearing apart the innards, which will allow me to kept my headlights factory/stock. +++