Comprehensive Component Monitor Diagnostic

Comprehensive component monitoring diagnostics are required to monitor emissions-related input and output powertrain components.

Input Components
The PCM 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, such as a TP sensor that indicates high throttle position at low engine loads or manifold absolute pressure (MAP) voltage. The input components may include, but are not limited to, the following sensors:
^ The vehicle speed sensor (VSS)
^ The mass air flow (MAF) sensor
^ The intake air temperature (IAT) sensor
^ The crankshaft position (CKP) sensor
^ The knock sensor (KS)
^ The TP sensor
^ The engine coolant temperature (ECT) sensor
^ The camshaft position (CMP) sensor
^ The 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 to enable Closed Loop fuel control.

Output Components
Diagnose the output components for the proper response to PCM 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 evaporative emission (EVAP) system
^ The electronic transmission controls
^ The A/C relay, if so equipped
^ The vehicle speed sensor (VSS) output
^ The malfunction indicator lamp (MIL) control
^ The cruise control enable, if so equipped