how to fix Honda Pilot Third Generation (2016-present) P0420 code

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent any electrical issues.
• Allow the vehicle to cool down if it has been running.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Disconnect the electrical connectors from both sensors.
  3. Remove the sensors using the O2 sensor socket.
  4. Install the new oxygen sensors and reconnect the electrical connectors.
  5. Torque the sensors to manufacturer specifications (usually around 30 lb-ft).

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, jack and jack stands, exhaust hanger removal tool.
• Sub-steps:
  1. Raise the vehicle using a jack and secure it with jack stands.
  2. Remove any heat shields if applicable to gain access to the catalytic converter.
  3. Disconnect the exhaust pipes from the catalytic converter by removing the bolts.
  4. Remove the catalytic converter by taking out the mounting bolts.
  5. Install the new catalytic converter, ensuring it is properly aligned and secured with bolts.
  6. Reinstall heat shields if removed.

4. Clear Error Codes

• Tools Required: OBD-II scanner.
• Sub-steps:
  1. Reconnect the battery.
  2. Use an OBD-II scanner to clear the P0420 code from the vehicle’s computer.
  3. Start the engine and check for any reoccurring codes.