Scan Tool Data Definitions

Scan Tool Data Definitions

Coolant Temperature
The scan tool displays -40 to +151°C (-40 to +304°F). This data is the coolant temperature the Instrument Cluster is attempting to display on the coolant temperature gage.
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 powertrain control module (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.
Cooling Fan Speed Command
The scan tool displays %. This parameter indicates the commanded state of the cooling fan.
Coolant Level Input
The scan tool displays OK or Low. If the ground circuit opens, the scan too will display Low.