Catalytic Converter: Testing and Inspection

THREE-WAY CATALYTIC CONVERTER (TWC) INSPECTION

CAUTION: Perform the following procedures if only DTC PO420 is detected.

NOTE: Make sure that no HO2S DTCs have been detected. If detected, this inspection is not applicable for TWC inspection.

1. Connect the M-MDS to the DLC-2.
2. Verify that the HO2S DTCs are not detected using the M-MDS.
- If an HO2S DTC is detected, perform the appropriate DTC inspection procedure. (See DTC TABLE.) Diagnostic Trouble Code Descriptions

3. Clear the DTC form the PCM memory using the M-MDS.
4. Start the engine and warm it up to normal operating temperature.
5. Verify that the engine compression is within the specification. (See COMPRESSION INSPECTION)
- If the compression pressure is not within the specification, repair or replace any malfunctioning part.

6. Drive the vehicle at Drive Mode 3. (See OBD-II DRIVE MODE) OBD-II Drive Mode
7. Access Test ID 10:21:80 using the "Diagnostic Monitoring Test Result" function.
8. Verify that the test result is within the specification as indicated on the M-MDS.
- If not as specified, replace the catalytic converter.