Install Instructions

Tools Needed

AutoTrix Universal 3rd Brake Light Flasher Diagram
  1. Locate and find access to your vehicle's 3rd brake light connector.
  2. Remove 3rd brake light housing or light fixture from vehicle. Our vehicle had 2 Phillips head screws attaching the 3rd brake light to the hatch. Separate the light housing from the vehicle in order to access the light connector.

  3. Remove the light connector from the light housing. Our vehicle had a white safety connector that we had to pry up before being able to remove the light connector from the light housing.

  4. Cut the 2 wires that are visible on the back of the connector and strip all 4 of the cut wire ends.

  5. This step requires a digital volt meter (DVOM) and another person to help operate the vehicle's brake pedal. The DVOM that we used was purchased at a local hardware store for about $12. Connect the black lead from the DVOM to a good ground on your vehicle's chassis. We were lucky enough to have a good ground close by in the screw head hole that held the light housing to the hatch of the vehicle. Have your helper press the brake pedal while you use the red lead from the DVOM to touch the exposed wire ends to verify which wire is the positive "hot" wire coming to the 3rd brake light. You will know you have found the positive wire when the DVOM reads approximately 12 volts. Take note of the color of wire that is found to be your vehicle's positive wire. Our vehicle's positive wire turned out to be brown with a yellow stripe and the negative wire was black. Once your positive wire is verified, your helper no longer needs to hold down the brake pedal.

  6. Crimp all of the butt connectors to all 4 of the cut wire ends; the 2 wires from your vehicle's 3rd brake light and the 2 wires from the light connector that you stripped earlier.
  7. Take the 3rd brake light flasher module and attach its wires with stripes to the connecter's wire ends. Note that the module's red wire with a white stripe needs to connect to your vehicle's verified positive wire color (verified in step 5) on the connector end and the module's black wire with a white stripe needs to connect to the remaining wire on the connector end. This can also be seen in the electrical diagram at the beginning of this install page.
  8. Take the 3rd brake light flasher module's remaining 2 wires (solid red and solid black) and attach them to your vehicle's remaining 3rd brake light wires. Again note that the module's solid red wire needs to connect to your vehicle's verified positive wire color and the module's solid black wire needs to connect to the last 3rd brake light wire.
  9. Before taping up your connections and reassembling everything, you need to test it to verify that it all works properly. Grab and hold the 3rd brake light housing, reattach the connector, and have your helper press your vehicle's brake pedal to verify that your brake light is flashing properly. Once your test is completed, your helper no longer needs to hold down the brake pedal.
  10. Tape all of the butt connectors and their connections from both ends of the module. Push the module into your vehicle's 3rd brake light cavity. The cavity on most vehicles should have enough space for the module and extra wire.

  11. Attach the light connector back to the 3rd brake light housing and reaffix the housing to the vehicle.

  12. If you are having any trouble with your installation, please feel free to Contact Us. You may also find posts from people who have installed our kits on www.ls1.com helpful, along with community input on your issue.