how to fix P0420 code in Honda Pilot YF4 (2023-Present)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to ensure safety.

2. Inspect and Replace Oxygen Sensors (if faulty)

• Tools Required: O2 sensor socket, wrench set, multimeter
• 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 and inspect for damage.
  4. If faulty, install new oxygen sensors and connect the electrical connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, exhaust pipe cutter, gasket scraper
• Sub-steps:
  1. Raise the vehicle and secure it with jack stands.
  2. Remove any heat shields covering the catalytic converter.
  3. Disconnect the exhaust pipes from the catalytic converter using a socket set.
  4. Inspect for any signs of blockage or damage; if necessary, cut and remove the old catalytic converter.
  5. Install the new catalytic converter using new gaskets and tighten bolts to manufacturer's specifications.
  6. Reinstall any heat shields previously removed.

4. Reset the Engine Control Module (ECM)

• Tools Required: OBD-II scanner
• Sub-steps:
  1. Reconnect the negative battery terminal.
  2. Use the OBD-II scanner to clear the P0420 code from the ECM.