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Comprehensive Component Monitor Diagnostics

Comprehensive component monitoring diagnostics are required in order to monitor the emissions-related input and output Powertrain components.

Input Components
The PCM monitors the input components for circuit continuity and for out-of-range values. The monitoring 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 sensor that indicates a high throttle position during low engine loads or during low MAP voltage. The input components may include but are not limited to the following sensors:
^ The Vehicle Speed (VSS) Sensor
^ The Accelerator Pedal Position (APP) sensor, if the vehicle has this equipment
^ The Mass Airflow (MAF) sensor
^ The Intake Air Temperature (IAT) sensor
^ 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

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 the closed loop fuel control.

Output Components
Diagnose the output components for the proper response to the PCM commands. Components where functional monitoring is not feasible will be monitored for circuit continuity and for out-of-range values if applicable.

The output components to be monitored include, but are not limited to, the following circuits:
^ The Idle Air Control (IAC) motor
^ The EVAP system
^ The electronic transmission controls
^ The A/C relay
^ The cooling fan relay
^ The VSS output
^ The MIL control
^ The cruise control inhibit, if the vehicle has this equipment