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Home >> Infiniti >> 2004 >> I35 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System >> DTC P0125: ECT Sensor >> Diagnostic Procedure
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Diagnostic Procedure

  1. CHECK ENGINE COOLANT TEMPERATURE SENSOR 

    Check resistance between engine coolant temperature sensor terminals 1 and 2 as shown in Figure .

    OK or NG 

    1. OK: GO TO 2.
    2. NG: Replace engine coolant temperature sensor.
  2. CHECK THERMOSTAT OPERATION 

    When the engine is cold [lower than 70° C (150° F)] condition, grasp lower radiator hose and confirm the engine coolant does not flow.

    OK or NG 

    1. OK: GO TO 3.
    2. NG: Repair or replace thermostat. Refer to THERMOSTAT .
  3. CHECK INTERMITTENT INCIDENT 
    1. : INSPECTION END