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Scan Tool Data Definitions

Scan Tool Data Definitions
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.