how to fix a P0420 code on Toyota Camry Seventh Generation (2012-2017)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to avoid electrical shorts.
• Allow the vehicle to cool down.

2. Inspect and Replace Oxygen Sensors

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

3. Inspect and Replace the Catalytic Converter (if necessary)

1. Remove the Catalytic Converter:
   • Locate the catalytic converter and remove the exhaust bolts using a socket set.
   • Support the exhaust system if necessary to prevent sagging.
2. Inspect the Catalytic Converter:
   • Check for any signs of damage, such as dents or a rattling sound indicating internal failure.
   • If damaged, replace it with a new catalytic converter.
3. Install the New Catalytic Converter:
   • Position the new catalytic converter and secure it with the bolts.
   • Torque the bolts to manufacturer’s specifications (typically around 30 lb-ft).

4. Clear the Codes and Test Drive

1. Reconnect the Battery:
   • Reconnect the battery terminals securely.
2. Clear the OBD-II Codes:
   • Use an OBD-II scanner to clear the P0420 code from the ECU.
3. Test Drive the Vehicle:
   • Drive the vehicle under various conditions to ensure that the check engine light does not reappear.