SFI SYSTEM, Diagnostic DTC:P0115 and P0116

DTC Code DTC Name
P0115 Engine Coolant Temperature Sensor 1 Circuit
P0116 Engine Coolant Temperature Sensor 1 Circuit Range / Performance

DESCRIPTION

A thermistor, whose resistance value varies according to the engine coolant temperature, is built into the engine coolant temperature sensor. The structure of the sensor and its connection to the ECM are the same as those of the intake air temperature sensor.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0115

Engine Coolant Temperature Sensor 1 Circuit

Change in engine coolant temperature sensor signal is outside threshold.

  • Engine coolant temperature sensor

  • Thermostat

  • Cooling system

  • Cooling fan system

  • Wire harness or connector

  • ECM

Comes on

DTC stored

P0116

Engine Coolant Temperature Sensor 1 Circuit Range / Performance

Change in engine coolant temperature sensor is small.

  • Engine coolant temperature sensor

  • Thermostat

  • Cooling system

  • Cooling fan system

  • Wire harness or connector

  • ECM

Comes on

DTC stored

MONITOR DESCRIPTION

These DTCs are stored when a malfunction is detected in any part related to the cooling system. If the change in the engine coolant temperature sensor value from when the engine was started until it is warmed up is small or outside of the threshold, the ECM will illuminate the MIL and store a DTC.

WIRING DIAGRAM

A331069E01

PROCEDURE

  1. INSPECT ENGINE COOLANT TEMPERATURE SENSOR

    1. Inspect the engine coolant temperature sensor.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR

    Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (ENGINE COOLANT TEMPERATURE SENSOR - ECM)

    1. Disconnect the engine coolant temperature sensor connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      B50-1 - B55-14 (THW)

      Always

      Below 1 Ω

      B50-2 - B55-26 (ETHW)

      Always

      Below 1 Ω

      B50-1 or B55-14 (THW) - Body ground and other terminals

      Always

      10 kΩ or higher

      B50-2 or B55-26 (ETHW) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK COOLING SYSTEM

    1. Check the cooling system.

      Click here

      Tip:

      Check the engine coolant level and the condition of the hoses. Check for engine coolant leaks.

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE COOLING SYSTEM

    OK

  4. CHECK COOLING FAN SYSTEM

    1. Check the cooling fan system.

      Click here

      Tip:

      Check the operating condition of the cooling fan.

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE COOLING FAN SYSTEM

    OK

  5. INSPECT THERMOSTAT

    1. Inspect the thermostat.

      Click here

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE ECM

    Click here

    NG

    REPLACE THERMOSTAT

    Click here