Coolant Temperature Sensor
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Coolant temperature sensor decreases in resistance as temperature rises and vice versa. ECM monitors the sensor voltage which varies as temperature changes the resistance value. As temperature rises, resistance through the sensor decreases, voltage drop of the sensor decreases, and input signal voltage also decreases (5-0 volts). Sensor should be tested using DISplus/GT1 multimeter. DISplus/GT1 multimeter ECM input should be 2.250 k/ohms at 68°F (20°C). Gauge input should be 6.7 k/ohms at 68°F (20°C).