what does P0420 code mean for my Honda Pilot YF3 (2016-2022)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the battery to avoid any electrical shorts.
• Ensure the vehicle is on a level surface and secure it with jack stands if needed.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the pre-catalytic oxygen sensor and the post-catalytic oxygen sensor.
  2. Disconnect the wiring harness from both sensors.
  3. Remove the sensors using an oxygen sensor socket.
  4. Install new oxygen sensors and torque to manufacturer specifications (usually around 30 ft-lbs).
  5. Reconnect the wiring harness.

3. Inspect and Replace Catalytic Converter

• Sub-steps:
  1. Locate the catalytic converter and inspect for damage or clogging.
  2. If necessary, remove the exhaust pipe bolts using a socket set.
  3. Disconnect any heat shields or brackets securing the catalytic converter.
  4. Remove the old catalytic converter and replace it with a new unit, ensuring proper alignment.
  5. Tighten all bolts to the specified torque (generally around 30 ft-lbs).
  6. Reinstall heat shields and any additional components removed.

4. Clear Error Codes

• Use the OBD-II scanner to clear the P0420 code from the ECM.
• Reconnect the battery if it was disconnected earlier.