Scan Tool Data Definitions

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Scan Tool Data Definitions
WARNING: This page is about a different car, the 2003 Buick Regal and 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.

IPC - Inputs - Coolant Hot Lamp:Β  The scan tool displays On or Off. The state of the engine coolant temperature indicator as commanded by the IPC.

PCM - ECT:Β  The scan tool displays -40 to +151Β°C (-40 to +304Β°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:Β  The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

PCM - FC Relay 1 Command:Β  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:Β  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:Β  The scan tool displays On or Off. This parameter indicates the state of the high speed fan relay driver.

RENDER: 1.0x

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