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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Replace O2 Sensors

Tools Required:

• O2 sensor socket
• Torque wrench

Steps:

1. Locate the upstream and downstream O2 sensors on the exhaust system.
2. Use the O2 sensor socket to remove the upstream O2 sensor.
3. Inspect the O2 sensor for damage or contamination.
4. Install the new O2 sensor and torque it to the manufacturer’s specifications (typically around 30 Nm).
5. Repeat the process for the downstream O2 sensor if necessary.

3. Inspect and Replace Catalytic Converter

Tools Required:

• Socket set
• Torque wrench
• Exhaust pipe cutter (if necessary)

Steps:

1. Visually inspect the catalytic converter for signs of damage, such as dents or rust.
2. If replacement is necessary, disconnect the exhaust pipes from the catalytic converter using the socket set.
3. Remove any mounting bolts and brackets holding the catalytic converter in place.
4. Install the new catalytic converter and reattach the exhaust pipes as necessary, ensuring all connections are tight.
5. Torque all bolts to the manufacturer’s specifications.

4. Clear Codes and Test Drive

Steps:

1. Reconnect the battery.
2. Use the OBD-II scanner to clear the P0420 code from the vehicle’s memory.
3. Start the engine and let it warm up.
4. Take the vehicle for a test drive to ensure the check engine light does not reappear.