Scan Tool Data Definitions

Scan Tool Data Definitions

Coolant Temperature: The scan tool displays -40°C to +151°C (40°F to +304°F). This data is the coolant temperature the Instrument Cluster is attempting to display on the coolant temperature gage.
ECT: The scan tool displays -40°C to +151°C (-40°F to +304°F). The Engine Coolant Temperature (ECT) sensor is mounted in the coolant stream. The 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.
Coolant Level Input: The scan tool displays OK or Low. If the ground circuit opens, the scan too will display Low.