For 1990-2009 cars
Low Coolant: The scan tool displays Yes or No. The scan tool displays Yes when the engine coolant is low.
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.
Fan Control 1 Command: The scan tool displays On or Off. This parameter indicates the state of the driver circuit for this device.
Fan Control 2 Command: The scan tool displays On or Off. This parameter indicates the state of the driver circuit for this device.
Fan Speed: The scan tool displays Low, Medium or High. This is the state of the cooling fans being commanded on by the PCM.
FC 1 Relay CKT Open Short to Ground: The scan tool displays Yes or No. Yes is displayed if the cooling fan 1 relay control circuit is open or shorted to ground.
FC 1 Relay CKT Short to Volts: The scan tool displays Yes or No. Yes is displayed if the cooling fan 1 relay control circuit is shorted to voltage.
FC 2 Relay CKT Open Short to Ground: The scan tool displays Yes or No. Yes is displayed if the cooling fan 2 relay control circuit is open or shorted to ground.
FC 2 Relay CKT Short to Volts: The scan tool displays Yes or No. Yes is displayed if the cooling fan 2 relay control circuit is shorted to voltage.