Test Description

The numbers below refer to the step numbers in the diagnostic procedures.

1. 1
   
   The Diagnostic System Check-Engine Controls prompts the technician to complete some basic tests and to store the Freeze Frame/Failure Records on the scan tool, if applicable.
2. 2
   
   If any other DTCs are set, diagnose those DTCs first. A fault in a component can cause the converter to appear degraded, or may have caused the failure.
3. 3
   
   Clearing the DTCs allows the catalyst test to be attempted 18 times, and completed up to 6 times during this key cycle. If the A/C is ON, the diagnostic may not run. The engine must be warmed. The converter needs to be warmed by raising the engine speed more than idle for the specified time prior to each attempted test. Check if the DTC passed or failed this key cycle. If the DTC does not pass or fail, look for a condition that could cause the test to abort.
4. 4
   
   This step includes tests for conditions that can cause the 3-way converter to appear degraded. Repair any conditions before proceeding with this table.
5. 9
   
   If the 3-way converter needs to be replaced, ensure that another condition which could damage the converter is not present. Conditions may include, misfire, high engine oil or coolant consumption, retarded spark timing, weak spark, or plugged or leaking injectors. Correct any possible causes of converter damage before replacing the converter.