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Home >> Hyundai >> 2009 >> Elantra GLS, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> DTC Troubleshooting Procedures >> DTC P0125 Insufficient Coolant Temperature For Closed Loop Fuel Control >> System Inspection
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System Inspection

  1. Coolant Level Inspection
    1. Check the cooling system coolant level.
    2. Is the coolant in the reservoir at the proper level?

      YES 

      • Go to  2

      NO 

  2. Thermostat Inspection
    1. Check if the thermostat bypass valve is stuck in the open position or if the correct type of thermostat was installed. Replace thermostat as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure
    2. Check the valve opening temperature of the thermostat

      Specification (Valve opening temperature):  80~84°C (176~183°F)

    3. If the opening temperature is not as specified, Replace thermostat as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.

      If OK, go to  3

  3. ECT Sensor Inspection
    1. Ignition "OFF"
    2. Disconnect ECTS connector
    3. Measure resistance between terminals 1 and 3 of the sensor connector (Component side)

      SPECIFICATION: 

      DTC P0125 RESISTANCE AND TEMPERATURE SPECIFICATIONS

      Temp. (°C) Resistance (kΩ) Temp. (°C) Resistance (kΩ)
      -20 14.1 ~ 16.8 40 Approx. 1.2
      0 Approx. 5.8 60 Approx. 0.6
      20 2.3 ~ 2.6 80 Approx. 0.3
      Fig 1: Measuring Resistance Between Terminals 1 And 3 Of Sensor Connector
      G05363796Courtesy of HYUNDAI MOTOR CO.
    4. Is resistance within the specification?

      YES 

      NO 

      • Check ECTS for contamination, deterioration, or damage. Substitute with a known-good ECTS and check for proper operation. If the problem is corrected, replace ECTS and then go to "VERIFICATION OF VEHICLE REPAIR " procedure