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Home >> Hyundai >> 2009 >> Santa Fe GLS, AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (Fuel System (2.7)) >> OBD-II review >> OBD-II system readiness tests >> Catalyst monitoring
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Catalyst monitoring

The catalyst efficiency monitor is a self-test strategy within the ECM or PCM that uses the downstream Heated Oxygen Sensor (HO2S) to determine when a catalyst has fallen below the minimum level of effectiveness in its ability to control exhaust emission.