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Coolant Temperature Sensor (CTS) & MAT Sensor

  1. Disconnect the electrical connector from the sensor. Using a high impedance, digital volt/ohmmeter, measure sensor resistance. If sensor resistance is not as specified, replace sensor. Refer to the CTS & MAT SENSOR TEMPERATURE-TO-RESISTANCE VALUE  table.
  2. Test electrical harness resistance of both sensors by testing between ECU harness connector "D-3" and sensor connector. Also test between sensor connector and ECU harness connector "C-10" ("C-8" on MAT sensor). Repair wire if open circuit is detected. Repair MAT sensor wiring harness if resistance is greater than one ohm.
CTS & MAT SENSOR TEMPERATURE-TO-RESISTANCE VALUE

°F(°C) Ohms
212 (100) 185
160 (71) 450
100 (38) 1600
70 (21) 3400
40 (4) 7500
20 (-7) 13,500
0 (-18) 25,000
-40 (-40) 100,700