why does my Tesla Model 3 Highland (2024-present) show error code B1402?

Solution

1. Preparation

• Tools Required: Tesla diagnostic tool, torque wrench, multimeter
• Ensure the vehicle is parked on a flat surface and the battery is at a safe temperature.
• Disconnect the vehicle from charging to prevent electrical hazards.

2. Inspect and Clean Battery Connections

• Sub-steps:
  1. Locate the battery terminals under the vehicle's rear cover.
  2. Use a socket set to carefully remove the terminal covers.
  3. Inspect the terminals for corrosion or damage. Clean them using a mixture of baking soda and water if corrosion is present.
  4. Reattach the terminals and torque them to the manufacturer’s specifications.

3. Check Battery Temperature Sensors

• Sub-steps:
  1. Access the battery management system via the diagnostic tool.
  2. Test the temperature sensors using a multimeter to ensure they are providing accurate readings.
  3. Replace any sensors that are faulty, using OEM parts only.

4. Update Battery Management Software

• Sub-steps:
  1. Connect the vehicle to Wi-Fi and ensure it is up to date with the latest software.
  2. Follow on-screen prompts to install any available updates related to the battery management system.

5. Reset Error Codes

• Sub-steps:
  1. After completing the repairs and updates, use the Tesla diagnostic tool to clear the error codes.
  2. Monitor the vehicle’s performance for any reoccurrence of the B1402 code.