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Anyone in Boston know how to replace LED system in tail light assembly?

Discussion in 'Gen 2 Prius Technical Discussion' started by bosprius11, Apr 6, 2018.

  1. bosprius11

    bosprius11 New Member

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    Location:
    Boston, MA
    Vehicle:
    2004 Prius
    Model:
    Two
    Hi all, I have a 2004 Prius that failed MA state inspection because the LED system in the passenger side tail light assembly is dim (though not out). Does anyone in the Boston area have experience replacing the LED system, or know of a shop that does? I'm trying to avoid bringing it to the dealership if possible.

    Any advice is appreciated. Thanks!
     
  2. dolj

    dolj Senior Member

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    The LED lights are not designed to be fixed once they give out, so replacement of the whole rear light assembly is the only official option.

    There is about one thread in the Gen 2 forums where a guy documented his disassembly and repair of one of his LED brake light clusters. After doing it once, his opinion was that he wouldn't do it again. It wasn't particularly difficult, but more tedious, especially around opening and then resealing the assembly.

    There are after market rear light assemblies, or you can fork out for a genuine Toyota OEM assembly.

    It is just one of those expensive fixes, when a whole-of-life unit fails.
     
  3. Stimp

    Stimp Member

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    Location:
    North Carolina
    Vehicle:
    2004 Prius
    Model:
    ----USA----
    Just bought a 2004 a couple months ago with a dim brake light. Bought a junkyard unit for $50 (tested it was fine before buying), but it's already getting dim. Now I'm working on repairing the original based on the repair dolj mentioned, which you can find here:

    instructables /id/Prius-Brake-Light-Repair/

    Only thing I'm doing differently is cutting access in the back of the light, not around the outer part. The lens is not removable with heat like lights from other manufacturers. An access port will be easier to seal later too. Used a soldering gun with a cutting blade instead of dremel - just personal preference, but the pieces fit together really well this way.

    Ordered these yesterday, an be an improvement over stock by eliminating the original resistor bank. Will be a $3 repair for each light. I'll post again when they arrive and are installed.

    lighthouseleds 5mm-12v-pre-wired-led-red-ultra-bright-15-000-mcd
     
  4. dolj

    dolj Senior Member

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    Seems strange that you should have two units that are dim, especially since the replacement unit tested good before install. Have you check the wiring for bad earth connections.
     
  5. Stimp

    Stimp Member

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    ----USA----
    I connected the original light (drivers side) to the passenger side harness and same results, passenger side light has been just fine throughout. Both sides have identical voltages with brakes engaged. I was also sceptical that the LEDs/resistor board could have gone bad, but that seems to be the case.
     
  6. Stimp

    Stimp Member

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    Vehicle:
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    ----USA----
    Did this fix, obviously far from perfect:

    DSC_1609.JPG

    Put this one in the car because the other was getting really dim. I think the next step is to replace the LEDS in the junkyard unit, wire them as taillights, change the taillight into a turn signal since it's red, and make the turn signal into a 7440/7443 red brake light. Just a matter of switching wires around and maybe getting an LED compatible blinker relay (since the 194 is lower wattage than the 7440 turn signal, or I might just get LED wedges). We'll see how that goes