Coolant Temperature Sensor/Switch (For Computer): Description and Operation

1993 Chevrolet S10/T10 P/U 2WD V6-173 2.8LSECTION Description and Operation

Engine Coolant Temperature (ECT) Sensor Circuit:






NOTE: Because different models and engine applications vary in wire colors, circuit numbers, and pin numbers, the above image is a typical example. Refer to COMPUTERS AND CONTROL SYSTEMS/SCHEMATIC AND ROUTING DIAGRAMS for specific schematic applications.

PURPOSE:

The Engine Coolant Temperature (ECT) sensor is a thermistor that is located in the engine coolant flow. When the coolant temperature is low, the sensor produces a high resistance. When the coolant temperature is high, the sensor produces a low resistance.

The control module sends a 5 volt signal to the ECT through a resistor in the computer and measures the voltage. The voltage will be high or low depending on coolant temperature. By varying the voltage the computer can determine engine coolant temperature.


RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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  • The engine overheats, stalls repeatedly, or misfires under load.
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