Engine

Engine

Engine Control - P0420 Catalyst System Efficiency below Threshold (Bank 1) - Monitor DTC Status

Monitor DTC Status

1. Check DTC Status
(1) Connect scantool to Data Link Connector (DLC).
(2) IG "ON".
(3) Select "DTC" button, and then Press "DTC Status" to check DTC's information from the DTCs menu.
(4) Read "DTC Status" parameter.








(5) Is parameter displayed "Present fault"?
YES
1) Substitute with a known - good Catalyst Converter and check for proper operation.
If the problem is corrected, Go to "Verification of Vehicle Repair" procedure.
NO
1) Go to "Component Inspection" procedure.