Intermittent brake light failure

Discussion in 'Gen 2 Prius Main Forum' started by james909, Oct 19, 2025 at 9:56 AM.

  1. james909

    james909 Junior Member

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    The led brake light went fully out pretty much on the offside. I disconnected and reconnected it and it was good again. Next day it's almost fully out again. Anyone had this problem and fixed it without replacing the whole unit. Anyone bought the AliExpress ones and had success. Mines the black variant.
     
  2. BiomedO1

    BiomedO1 Senior Member

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    Sorry, need more information. Do you mean that you replaced the OEM incandescent bulbs with aftermarket LED bulbs? Now the brake and turn signals lamps are intermittent or flash quickly???
    What happens when you put the OEM incandescent back in????????
     
  3. james909

    james909 Junior Member

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    It came with LEDs. Shown working here but now the offside is not working. IMG-20251018-WA0006.jpeg
     

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  4. james909

    james909 Junior Member

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    It's oem. I haven't replaced it but might have to if it keeps stopping working
     
  5. BiomedO1

    BiomedO1 Senior Member

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    they seem to be incandescence bulbs on this side of the pond; check for leaks and loose connections. I spray mine with contact cleaner and use dielectric grease them into the socket, so moisture can't get in there to mess with the conductivity.
    YouTube has videos on how to do this.
     
  6. dolj

    dolj Senior Member

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    Not on Gen 2. Gen 2 shipped with a LED cluster.
     
  7. ChapmanF

    ChapmanF Senior Member

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    In gen 2, the taillight, side marker, turn signal/hazard, and back-up lights are replaceable bulbs. The stop, or brake, lights are LEDs built into the housing.

    [​IMG]

    They give that neat effect you can see in the photo in #3, where when the brake lights are off, that part of the combo light appears to match the dark glass across the hatch. The plastic lens isn't tinted or darkened at all, so the brake lights don't lose any brightness, but when they're off you're seeing the black surfaces below the reflectors.

    Then with the refresh in (2006, I think?) they gave up on that effect and made those surfaces silver instead of black.
     
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  8. Tombukt2

    Tombukt2 Senior Member

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    I only use the 04 05 tails on all my gen2 have about six sets . When I get a second series Gen 2 that's the first change that's made the blk tails . Then the painted interior dash in wine and door panels to match no grained vinyl in mine
     
  9. Tombukt2

    Tombukt2 Senior Member

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    I think it may be something to do with that circuit board that runs those led . The aftermarket as you covered for like 46 bucks so it's not really worth it trying to fiddle with too much but I do prefer the Stanley branded originals but the aftermarkets work fine their lens is just kind of trifiling