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Diagnostic Procedures

  1. Perform POWERTRAIN ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK , then go to next step.
  2. Turn ignition on. Using scan tool, check if other DTCs are present. If other DTCs are present, diagnose affected DTCs first. If other DTCs are not present, go to next step.
  3. Check exhaust system for leaks, damage, loose or missing hardware. Repair as necessary. After repairs, go to step 5). If exhaust system is okay, go to next step.
  4. Ensure original 3-way catalytic converter is installed. Check catalytic converter for damage or tampering. Ensure oxygen sensors are properly installed and wiring and connections are okay. Repair or replace components as necessary. After repairs, go to next step. If components are okay, go to step 6).
  5. Using scan tool, select DTC INFO then DTC STATUS under DTC mode. Operate vehicle under which DTC was set. Observe scan tool display of DTC STATUS, looking for DTC to run or fail. If this DTC failed, go to next step. If this DTC did not fail, system is okay.
  6. Replace catalytic converter.
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