Component Inspection

Engine

Engine Control - P0420 Catalyst System Efficiency below Threshold (Bank 1) Component Inspection

Component Inspection

Monitor the Catalyst Converter
1. Clear DTC.
2. Start the engine and warm it up until the radiator fan comes on. (more than at least 10 minutes).
3. Drive at a steady speed between 45-55 mph (72-88 km/h) for 30 seconds.
4. Stop and then maintain idle state for 120 seconds in D-position.
5. Repeat step 3 once again.
6. Stop and then keep it in idle state (D-position) for 120 seconds.
7. Repeat step 3 once again.
8. Stop and then maintain idle state for 120 seconds in D-position.
9. IG "OFF".
10. Repeat steps 3 through 9 three times.
11. Check if catalyst monitoring readiness is complete. so, if the readiness is incomplete, repeat steps 2 through 10.
12. Does the scan tool show DTC P0420?