how to fix P0420 code on Honda CR-V Fifth Generation (2017-2022)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shorts during repairs.
• Allow the vehicle to cool down completely before working on the exhaust system.

2. Inspect and Replace O2 Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench, multimeter.
• Sub-steps:
  1. Locate the upstream and downstream O2 sensors. They are usually located on the exhaust manifold (upstream) and before the catalytic converter (downstream).
  2. Disconnect the electrical connectors from both sensors.
  3. Using the O2 sensor socket, remove the upstream O2 sensor first.
  4. Install the new upstream O2 sensor and tighten to the manufacturer’s specifications (usually around 30-40 lb-ft).
  5. Repeat the process for the downstream O2 sensor.
  6. Reconnect the electrical connectors to both sensors.

3. Check and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, exhaust hanger removal tool.
• Sub-steps:
  1. Raise the vehicle securely on jack stands and remove any underbody covers if applicable.
  2. Disconnect the exhaust pipes from the catalytic converter using a socket set.
  3. Remove any exhaust hangers attached to the catalytic converter using an exhaust hanger removal tool.
  4. Remove the catalytic converter from the vehicle.
  5. Install the new catalytic converter by reversing the removal steps, ensuring all connections are tight and secure.
  6. Torque all bolts to the manufacturer’s specifications.

4. Reconnect Battery and Clear Codes

• Reconnect the battery terminals.
• Use an OBD-II scanner to clear the P0420 code and any other stored codes.