how to troubleshoot my Tesla Model 3 Highland (2024-present) brake lights not working

Solution

1. Preparation

• Gather necessary tools: OBD-II scanner (if applicable), multimeter, basic hand tools (screwdriver, socket set).
• Ensure the vehicle is parked on a flat surface and the ignition is off.
• Disconnect the vehicle from any charging source.

2. Inspect and Replace Brake Pedal Switch

1. Locate the brake pedal switch, typically mounted above the brake pedal.
2. Disconnect the electrical connector from the brake pedal switch.
3. Using a multimeter, test for continuity when the brake pedal is pressed. If there is no continuity, the switch is faulty and needs replacement.
4. Remove the old brake pedal switch by unscrewing it from its mounting bracket.
5. Install the new brake pedal switch by reversing the removal process.
6. Reconnect the electrical connector to the new switch.

3. Check Wiring and Connections

1. Inspect the wiring harness connected to the brake lights for any signs of wear, fraying, or corrosion.
2. If any damage is found, repair or replace the affected wiring.
3. Ensure all connectors are securely fastened and free of corrosion.

4. Test the Brake Lights

1. After completing the above repairs, have a second person press the brake pedal while you observe the brake lights.
2. If the lights work, proceed to reset any fault codes using the OBD-II scanner or Tesla app, if applicable.