ECT Sensor: The scan tool displays -40 to +151°C (-40
to +304°F). The engine coolant temperature (ECT) sensor is mounted in the coolant
stream. The powertrain control module (PCM) applies 5 volts to
the ECT sensor circuit. The sensor is a thermistor which changes internal resistance
as temperature changes. When the sensor is cold (internal resistance high), the
PCM monitors a high signal voltage and interprets it as a cold engine. As the sensor
warms (internal resistance decreases), the voltage signal decreases and the PCM interprets
the lower voltage as a warm engine.
FC Relay 1 Command: The scan tool displays ON or OFF. This
parameter indicates the state of the driver circuit for this device.
FC Relay 2 and 3 Command: The scan tool displays ON or OFF.
This parameter indicates the state of the driver circuit for this device.
FC Relay 1 Circuit Status: The scan tool displays OK or Fault.
This parameter indicates the status for the state of the driver circuit for this device.
FC Relay 2 and 3 Circuit Status: The scan tool displays OK or
Fault. This parameter indicates the status for the state of the driver circuit for
these devices.