Scan Tool Data Definitions

Scan Tool Data Definitions
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 Powertrain Control Module (PCM) applies 5 volts to the ECT sensor signal circuit. The sensor is a thermistor which changes internal resistance as temperature changes. When the sensor is cold and the internal resistance is high, the PCM monitors a high signal voltage and interprets it as a cold engine. As the sensor warms and the internal resistance decreases, the voltage signal decreases and the PCM interprets the lower voltage as a warm engine.
FC Relay 1 Command
The fan control (FC) relay is commanded by the PCM. FC Relay 1 displays the command as ON or OFF.
Low Coolant Lamp
The scan tool displays ON or OFF. The state of the Low Coolant indicator as commanded by the IPC. The IPC receives a class 2 message from the BCM indicating the coolant level.
Low Coolant Level
The scan tool displays ON or OFF. The state of the low coolant level switch.