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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical issues.
• Raise the vehicle securely on jack stands.

2. Inspect and Replace Oxygen Sensors

1. Locate the oxygen sensors: Identify the upstream (pre-catalytic converter) and downstream (post-catalytic converter) oxygen sensors.
2. Remove the upstream oxygen sensor:
   • Use an oxygen sensor socket and ratchet to unscrew the sensor.
   • Disconnect the wiring harness from the sensor.
3. Install the new upstream oxygen sensor:
   • Apply anti-seize compound on the threads of the new sensor.
   • Screw in the new sensor and tighten it to the manufacturer’s specifications (usually around 30 lb-ft).
   • Reconnect the wiring harness.
4. Repeat for the downstream oxygen sensor using the same process.

3. Inspect and Replace the Catalytic Converter

1. Remove the catalytic converter:
   • Disconnect the exhaust pipes from the catalytic converter using a socket set.
   • Unscrew the mounting bolts securing the catalytic converter to the exhaust system.
   • Carefully remove the catalytic converter from the vehicle.
2. Inspect the new catalytic converter:
   • Ensure that the new catalytic converter matches the original specifications.
3. Install the new catalytic converter:
   • Position the new catalytic converter and secure it with the mounting bolts.
   • Reattach the exhaust pipes and tighten the bolts to manufacturer specifications (typically 30-40 lb-ft).
4. Reconnect the negative battery terminal.