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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working.
• Raise the vehicle using a jack and secure it on jack stands.

2. Inspect and Replace Oxygen Sensors

1. Locate the Oxygen Sensors: Identify the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
2. Remove the Sensors:
   • Use an oxygen sensor socket or wrench to carefully unscrew the sensors.
   • Disconnect the electrical connectors.
3. Install New Sensors:
   • Apply anti-seize compound on the threads of the new oxygen sensors.
   • Install the new sensors and connect the electrical connectors.
   • Torque the sensors to the manufacturer's specifications (typically around 30 lb-ft).

3. Inspect and Replace Catalytic Converter (if necessary)

1. Remove Exhaust Components:
   • Unbolt the exhaust pipes connected to the catalytic converter using a socket set.
   • Support the exhaust system to prevent damage while removing the converter.
2. Inspect the Catalytic Converter:
   • Check for signs of physical damage, clogging, or excessive carbon buildup.
3. Install New Catalytic Converter:
   • Position the new catalytic converter in place.
   • Reattach exhaust pipes and secure with bolts, tightening to the manufacturer's torque specifications (usually around 40 lb-ft).
4. Replace any gaskets or seals to prevent leaks.

4. Reset the Check Engine Light

• Reconnect the battery.
• Use the OBD-II scanner to clear the P0420 code from the system.