FixVault
Home › Chrysler › 2001 › PT Cruiser Base, Automatic › Repair and Diagnosis › Engine Performance › System › Engine Controls - Self-Diagnostics › Diagnostic Tests › DTC P0420: 1/1 Catalytic Converter Efficiency › Testing

DTC P0420: 1/1 Catalytic Converter Efficiency: Testing

  1. Turn ignition on. Using scan tool, read DTCs. If GOOD TRIP is displayed and equal to zero, go to step  3 . If GOOD TRIP is not displayed and equal to zero, go to next step.
  2. Conditions that set DTC are not present at this time. Using scan tool, read freeze frame data. Using this data, attempt to duplicate conditions that set DTC. If DTC resets, go to next step. If DTC does not reset, test is complete.
  3. Check exhaust for excessive smoke caused by an internal engine problem. If no engine mechanical problems are present, go to next step. If any engine mechanical problems are present, repair as necessary then replace catalytic converter.
  4. Start engine and let it idle. Check for exhaust leaks between engine and downstream HO2S. Repair exhaust system as necessary. If no leaks are found, go to next step.
  5. Review repair history. If downstream HO2S has been replaced without replacing upstream HO2S, replace upstream HO2S. If downstream HO2S has not been replaced recently or downstream HO2S has been replaced along with upstream HO2S, go to next step.
  6. If no other possible causes are remaining, replace catalytic converter.
About FixVault