how to fix P0420 code on my Ram 1500 DT (2019-Present)?

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the vehicle battery to ensure safety while working.

2. Inspect and Replace Oxygen Sensors

1. Locate the Oxygen Sensors: Identify the upstream and downstream oxygen sensors in the exhaust system.
2. Remove the Sensors:
   • Use a wrench or oxygen sensor socket to unscrew and remove both sensors from their respective locations.
3. Install New Sensors:
   • Apply anti-seize compound on the threads of the new oxygen sensors.
   • Screw the new sensors into place and tighten them to the manufacturer's specifications (usually around 30 lb-ft).
4. Reconnect the Battery: Reconnect the battery once the sensors are replaced.

3. Replace Catalytic Converter (if needed)

1. Remove Exhaust Components:
   • Use a socket set to unbolt the exhaust components connected to the catalytic converter.
   • Support the exhaust system to prevent strain on other components.
2. Remove the Catalytic Converter:
   • Disconnect the catalytic converter from the exhaust pipes.
   • If it's welded, use a cutting tool to carefully remove it.
3. Install New Catalytic Converter:
   • Position the new catalytic converter and secure it with the provided hardware.
   • Ensure all seals and gaskets are properly positioned to prevent leaks.
4. Reassemble Exhaust System:
   • Reconnect all exhaust components, ensuring all bolts are tightened to the specified torque values.