Comprehensive Component Monitor Diagnostic

The comprehensive component monitoring diagnostics are required to monitor emissions-related input and output Powertrain components. The California Air Resources Board (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