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Scan Tool Data Definitions

WARNING: This page is about a different car, the 2007 Pontiac Montana SV6, 2007 Chevrolet Uplander, and 2007 Buick Terraza. However, it is still accessible from the selected car via links, so may be relevant.
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 engine control module (ECM) 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 ECM 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 ECM 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.

Ignition 1 Signal

The scan tool displays Voltage. This parameter indicates the status of voltage at the ECM.