Input Devices: Notes

Input devices are monitored for circuit continuity and out-of-range values, which includes rationality checking. Rationality checking will indicate a fault when a sensor signal does not seem reasonable based on other input signals.

Input devices may include, but are not limited to the following sensors:

• A/C compressor control module (A/C relay)
• Camshaft Position (CMP) sensor
• Closed Throttle Position (CTP) switch
• Clutch Pedal Position (CPP) switch
• Crankshaft Position (CKP) sensor
• Electrical Load Idle-Up Signal
• Engine Coolant Temperature (ECT) sensor. In addition to circuit continuity and rationality check, ECT sensor is monitored to ensure its ability to maintain a constant temperature, enabling closed loop fuel control.
• Fuel level sensor
• Fuel Tank Pressure (FTP) sensor
• Heated Oxygen Sensor (HO2S)
• Knock (KS) sensor
• Mass Airflow (MAF) sensor
• Manifold Absolute Pressure (MAP) sensor
• Power Steering Pressure (PSP) switch
• Throttle Position (TP) sensor
• Transaxle Range (TR) switch
• Vehicle Speed Sensor (VSS)

Vehicles are equipped with different combinations of input devices. Not all devices are used on all models. To determine input device usage on a specific model, see WIRING DIAGRAMS article.