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Comprehensive Component Monitor Diagnostic Operation

The comprehensive component monitoring diagnostics are required to monitor emissions-related input and output Powertrain components. The CARB OBD II Comprehensive Component Monitoring List of Components Intended To Illuminate The MIL is a list of components, features or functions that could fall under this requirement.

Input Components
The control module monitors the input components for circuit continuity and out-of-range values. This includes performance checking. Performance checking refers to indicating a fault when the signal from a sensor does not seem reasonable, for example, a Throttle Position (TP) sensor that indicates high throttle position at low engine loads or MAP voltage. The input components may include but are not limited to the following sensors:
- The Vehicle Speed Sensor (VSS)
- The Crankshaft Position (CKP) sensor
- The Knock Sensor (KS)
- The Throttle Position (TP) sensor
- The Engine Coolant Temperature (ECT) sensor
- The Camshaft Position (CMP) sensor
- The Manifold Absolute Pressure (MAP) sensor
- The Mass Air Flow (MAF) sensor

In addition to the circuit continuity and rationality check, the ECT sensor is monitored for its ability to achieve a steady state temperature in order to enable a closed loop fuel control.

Output Components
The Output Components respond to control module commands. Components where functional monitoring is not feasible will be monitored for circuit continuity and out-of-range values if applicable.

Output components to be monitored include, but are not limited to the following circuits:
- The Idle Air Control (IAC) Motor
- The Control module controlled EVAP Canister Purge Valve
- The Electronic transmission controls
- The A/C relay
- The Cooling fan relay
- The VSS output The MIL control
- The Cruise control inhibit

California Air Resources Board (CARB) OBD II Comprehensive Component Monitoring List of Components Intended to Illuminate MIL

IMPORTANT: Not all vehicles have these components.

- Transmission Range (TR) Mode Pressure Switch
- Transmission Turbine Speed Sensor (HI/LO)
- Transmission Vehicle Speed Sensor (HI/LO)
- Ignition Sensor (Cam Sync, Diag)
- Ignition Sensor Hi Res (7x)
- Knock Sensor (KS)
- Engine Coolant Temperature (ECT) Sensor
- Intake Air Temperature (IAT) Sensor
- Throttle Position (TP) Sensor A, B
- Manifold Absolute Pressure (MAP) Sensor
- Mass Air Flow (MAF) Sensor
- Automatic Transmission Temperature Sensor
- Transmission Torque Converter Clutch (TCC) Control Solenoid
- Transmission TCC Enable Solenoid
- Transmission Shift Solenoid A
- Transmission Shift Solenoid B
- Transmission 312 Shift Solenoid
- Ignition Control (IC) System
- Idle Air Control (IAC) Coil
- Evaporative Emission Purge Vacuum Switch
- Evaporative Emission Canister Purge (EVAP Canister Purge)