Circuit/System Testing
NOTE:
A new converter with less than 100 miles on it may set DTC P0420 or P0430 due to out-gassing of the internal matting. Operating the vehicle at highway speeds for approximately 1 hour may correct the condition.
- Engine idling, observe the DTC information with a scan tool. Verify there are no HO2S or misfire DTCs set.
- If a DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle to diagnosis the applicable DTC, before proceeding with this diagnostic procedure.
- Verify the following conditions do not exist with the catalytic converter:
- Dents
- A severe discoloration caused by excessive temperatures
- Road damage
- An internal rattle caused by damaged catalyst substrate
- Restrictions
- If a condition is found, replace the catalytic converter.
- Verify the following conditions do not exist with the exhaust system:
- Leaks
- Physical damage
- Loose or missing hardware
- If a condition is found, repair the exhaust system.
- Verify the following conditions do not exist with the HO2S 2:
- The HO2S is not at the correct torque
- Damage
- If a condition is found, replace the appropriate B52 HO2S 2.
- Engine idling, increase engine speed to 1, 500 RPM for 1 minute and then return to a stabilized idle. Observe HO2S 1 and 2 voltage parameters with a scan tool. HO2S 1 voltage should be more active than HO2S 2.
- If HO2S 2 is as active as HO2S 1, replace the catalytic converter.