2021 Tundra 3rd Brake Light Wiring

Just picked up GFC early Jan and finally got around to wiring the 3rd brake light. In case this is helpful for anyone else.

  1. Remove tailight: this video shows which bolts and how to pull it off: New Tail lights for my New Tundra! 2014-2021 Tundras! - YouTube
    The bottom connection on the taillight is the brake lights. middle is reverse, top is turn signals.
  2. run wire through small hole in bed
  3. Use wire tap connectors to tap red to the blue wire (brake) and black to the white wire (ground)
  4. put it all back together


Matched the same wires for my 2018 Tacoma and works like a charm!!! Thanks for the photo!
Was conflicting from the video that shows black to the green wire instead :thinking:
No fuse issues at all going black to white/black.

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