how to fix P0420 code on Toyota Camry XV70 (2018-2024)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool before working on the exhaust system.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, torque wrench
• Remove the electrical connectors from both the upstream and downstream oxygen sensors.
• Using an O2 sensor socket, unscrew and remove the sensors.
• Install new oxygen sensors by reversing the removal steps, ensuring they are torqued to manufacturer specifications (typically around 30 ft-lbs).

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, jack and jack stands, cutting tool (if needed), exhaust sealant
• Lift the vehicle and secure it on jack stands.
• Disconnect the exhaust pipe from the catalytic converter, removing any hangers and bolts.
• If the converter is welded in place, use a cutting tool to remove it.
• Install the new catalytic converter, ensuring all gaskets are replaced.
• Reconnect the exhaust pipe and secure all hangers and bolts, torquing to factory specifications.

4. Clear Codes and Test Drive

• Reconnect the battery.
• Use an OBD-II scanner to clear the P0420 code from the system.
• Take the vehicle for a test drive under various conditions to ensure that the engine and exhaust systems are functioning properly.