how to diagnose B0020 code on Toyota Highlander Third Generation (2014-2019)

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, basic socket set, and electrical contact cleaner.
• Safety Warnings: Disconnect the negative battery terminal before working on the airbag system to prevent accidental deployment.

2. Inspect and Repair Wiring

• Sub-steps:
  1. Remove the appropriate trim panels to access the airbag wiring harness.
  2. Visually inspect the wiring for fraying, cuts, or corrosion.
  3. If damage is found, repair or replace the wiring as necessary using solder and heat shrink tubing or appropriate connectors.
  4. Use electrical contact cleaner on connectors, ensuring they are clean and secure.

3. Replace Airbag Module (if necessary)

• Sub-steps:
  1. If the airbag module is deemed faulty, disconnect the battery again.
  2. Remove the airbag module from its mounting location, typically located under the dashboard.
  3. Disconnect the electrical connectors from the airbag module.
  4. Install the new airbag module by connecting the electrical connectors and securing it in place.
  5. Reconnect the battery.

4. Final Checks

• Sub-steps:
  1. Reconnect the negative battery terminal.
  2. Use the OBD-II scanner to check for any remaining codes.
  3. Conduct a visual inspection of all connections and ensure everything is secured properly.