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Monitored Emission Control Systems

WARNING: This page is about a different car, the 2003 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.

The OBD-II System monitors all emission control systems that are on-board. Not all vehicles have a full complement of emission control systems. For example, a vehicle may not be equipped with AIR or EGR. The OBD-II regulations require monitoring of the following:

For the specific DTCs required for each system, refer to Inspection/Maintenance System DTC. See INSPECTION/MAINTENANCE SYSTEM DTCS  table under INSPECTION/MAINTENANCE COMPLETE SYSTEM SET PROCEDURE. Systems such as fuel delivery, misfire, and comprehensive components may not be listed in a system status list. These tests run continuously on some vehicles and may not require an indicator.