Monitored Emission Control Systems
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:
- Air Conditioning System
- Catalytic converter efficiency
- Comprehensive component monitoring - Emission related inputs and outputs
- Evaporative Emissions (EVAP) System
- Exhaust Gas Recirculation (EGR) System
- Fuel Delivery System
- Heated catalyst monitoring
- Misfire monitoring
- Oxygen Sensor System (O2S or HO2S)
- Oxygen Sensor Heater System (HO2S Heater)
- Secondary Air Injection (AIR) System
For the specific DTCs required for each system, refer to Inspection/Maintenance (I/M) System DTC Table . 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.