how to fix P0420 code on my Toyota RAV4 XA40 (2013-2018)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety while working on electrical systems.

2. Inspect and Replace Oxygen Sensors

• 2.1. Remove the upstream oxygen sensor:

  • Use an oxygen sensor socket to unscrew the sensor from the exhaust manifold.
  • Disconnect the electrical connector.

• 2.2. Install the new upstream oxygen sensor:

  • Apply anti-seize compound to the threads (if required).
  • Screw in the new sensor and reconnect the electrical connector.

• 2.3. Repeat for the downstream oxygen sensor:

  • Use the same procedure to remove and replace the downstream oxygen sensor located near the catalytic converter.

3. Inspect and Replace the Catalytic Converter

• 3.1. Remove the exhaust components:

  • Unbolt the exhaust pipe or manifold connected to the catalytic converter.
  • Ensure all gaskets are removed and inspect for damage.

• 3.2. Install the new catalytic converter:

  • Position the new catalytic converter in place, ensuring proper alignment.
  • Use new gaskets to prevent leaks and bolt the exhaust components back together, tightening to manufacturer's specifications (typically around 30-40 lb-ft).

4. Clear Codes and Test Drive

• 4.1. Reconnect the battery terminal.
• 4.2. Use the OBD-II scanner to clear the P0420 code.
• 4.3. Test drive the vehicle for at least 20-30 minutes to ensure the check engine light does not return.