Scan Tool Data Definitions

WARNING: This page is about a different car, the 2004 Buick Regal and 2004 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.

IPC - Inputs - Coolant Hot Lamp: The scan tool displays On or Off. The state of the engine coolant temperature indicator as commanded by the IPC.
PCM - ECT: 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 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.
PCM - FC Relay 1 Circuit Status: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.
PCM - FC Relay 1 Command: The scan tool displays On or Off. This parameter indicates the state of the low speed fan relay driver.
PCM - FC Relay 2 and 3 Circuit Status: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.
PCM - FC Relay 2 and 3 Command: The scan tool displays On or Off. This parameter indicates the state of the high speed fan relay driver.