Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

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Link: lemon-manuals.la or lemon-manuals.org.ua

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Scan Tool Data Definitions

Scan Tool Data Definitions
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.