Input and Output Components

CARB OBD II Comprehensive Monitoring List Of Components Intended To Illuminate MIL:

INPUT COMPONENTS
Input components are monitored for circuit continuity and out-of-range values. This includes rationality checking. Rationality checking refers to indicating a fault when the signal from a sensor does not seem reasonable (i.e. a Throttle Position (TP) sensor that indicates high throttle position at low engine loads or MAP voltage). Input components may include, but are not limited to the following sensors:

^ Vehicle Speed Sensor (VSS)
^ Crankshaft Position (CKP) sensor
^ Knock Sensor (KS)
^ Throttle Position (TP) sensor
^ Engine Coolant Temperature (ECT) sensor
^ Camshaft Position (CMP) sensor
^ Manifold Absolute Pressure (MAP) sensor
^ 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 to enable closed loop fuel control.

OUTPUT COMPONENTS
Output components are diagnosed for proper response 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:

^ Idle Speed Control (ISC) Motor
^ Control module controlled EVAP Canister Purge Valve
^ Electronic Transaxle controls
^ A/C relay
^ Cooling fan relay
^ VSS output
^ MIL control
^ Cruise control inhibit