For 1990-2009 cars
ECT: The scan tool displays 39-140°C (100-284°F). The PCM monitors the voltage at the signal circuit of the engine coolant temperature sensor. The voltage is inversely proportional to the engine coolant temperature.
Engine Oil Life Remaining: The scan tool displays 0-100%. The PCM calculates the remaining engine oil life.
Engine Oil Pressure Sensor: The scan tool displays 0-5 Volts. The scan tool displays engine oil pressure in volts. The PCM monitors the engine oil pressure signal circuit. The scan tool displays low engine oil pressure as low voltage.
Engine Speed: The scan tool displays 0-9999 RPM. Engine speed is computed by the PCM from the 3X reference input. The engine speed should remain close to desired idle under various engine loads with the engine idling.
Ignition 1 Signal: The scan tool displays 0-25 Volts. The PCM monitors the voltage of the ignition 1 voltage circuit.
MIL Command: The scan tool displays On/Off. The scan tool will indicate On when the malfunction indicator lamp is commanded On by the PCM.
Reduced Engine Power: The scan tool displays Active/Inactive. The scan tool displays Active when the throttle actuator control (TAC) system detects a malfunction.The PCM receives a signal from the TAC module.
Vehicle Speed: The scan tool displays 0-255 km/h (0-158 mph). The PCM monitors the voltage at the signal circuit of the vehicle speed sensor. The voltage is proportional to the vehicle speed.