Input Devices: Notes
NOTE:
Components are grouped into 2 categories. The first category covers INPUT DEVICES, which control or produce voltage signals monitored by the control unit. The second category covers OUTPUT SIGNALS, which are components controlled by the control unit.
The PCM supplies a buffered (reference) voltage to the various information sensors and switches. PCM monitors the input components for circuit continuity and out-of-range values. PCM also provides performance checking. Performance checking refers to the PCM indicating a fault when the signal from an input does not seem reasonable, i.e., a Throttle Position (TP) sensor that indicates a high throttle position at low engine loads or low manifold absolute pressure sensor voltage. The input components may include, but are not limited to the following sensors and switches:
- A/C compressor clutch relay (A/C relay).
- Camshaft Position (CMP) sensor.
- Crankshaft Position (CKP) sensor.
- Engine Coolant Temperature (ECT) sensor.
- Fuel Tank Pressure (FTP) sensor.
- Heated Oxygen Sensor (HO2S).
- Knock Sensor (KS).
- Mass Air Flow (MAF) sensor.
- Power Steering Pressure (PSP) switch, if equipped.
- Transmission Range Switch (A/T only).
- Throttle Position (TP) sensor.
- Vehicle Speed Sensor (VSS).