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Home >> Geo >> 1994 >> Prizm Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Computerized Engine Controls >> Engine Sensors & Switches >> Engine Coolant Temperature (ECT) Sensor
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Engine Coolant Temperature (ECT) Sensor

  1. A malfunction in the engine coolant temperature sensor circuit will set a related diagnostic trouble code. For testing procedures, see TESTS W/CODES article in this section. An out-of-calibration ECT sensor may not set a diagnostic trouble code. Use following procedure to test sensor calibration.
  2. Remove engine coolant temperature sensor. Refer to the ENGINE COOLANT TEMPERATURE (ECT) SENSOR LOCATION  . Using ohmmeter, measure resistance of engine coolant temperature sensor at designated temperatures. Replace ECT sensor if resistance is not within specification. See ENGINE COOLANT TEMPERATURE (ECT) SENSOR RESISTANCE  .
ENGINE COOLANT TEMPERATURE (ECT) SENSOR LOCATION

Application Location
Prizm & Prizm LSi On Left Side Of Engine, In Coolant Housing
ENGINE COOLANT TEMPERATURE (ECT) SENSOR RESISTANCE

Temperature: °F (°C) Ohms
-4 (-20) 10,000-20,000
32 (0) 4000-7000
68 (20) 2000-3000
104 (40) 900-1300
140 (60) 400-700
176 (80) 200-400