Scan Tool Data Definitions

WARNING: This page is about a different car, the 2002 Pontiac Bonneville. However, it is still accessible from the selected car via links, so may be relevant.

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 Circuit Status: The scan tool displays OK or Fault. This parameter indicates the diagnostic state of the of the output driver for the FC relay 1 circuit.

FC Relay 1 Command: The scan tool displays On or Off. This parameter indicates the commanded state of the FC relay 1.

FC Relay 2 and 3 Circuit Status: The scan tool displays OK or Fault. This parameter indicates the diagnostic state of the output driver for the FC relay 2 and 3 circuit.

FC Relay 2 and 3 Command: The scan tool displays On or Off. This parameter indicates the commanded state of the FC relay 2 and 3.