SFI SYSTEM, Diagnostic DTC:P0116

DTC Code DTC Name
P0116 Engine Coolant Temperature Circuit Range / Performance Problem

DESCRIPTION

Refer to DTC P0115 Click here.

DTC No. DTC Detection Condition Trouble Area
P0116

The engine coolant temperature is between 35°C and 60°C (95°F and 140°F) when the engine is started, and conditions (a) and (b) are met (2 trip detection logic):


  • (a) The vehicle is driven at varying speeds (accelerated and decelerated).

  • (b) The engine coolant temperature remains within 3°C (5.4°F) of the initial engine coolant temperature.

  • Water inlet with thermostat

  • Engine coolant temperature sensor

MONITOR DESCRIPTION

The engine coolant temperature sensor is used to monitor the engine coolant temperature. The engine coolant temperature sensor has a built-in thermistor with a resistance that varies according to the temperature of the engine coolant. When the engine coolant temperature is low, the resistance of the thermistor increases. When the temperature is high, the resistance drops. These variations in the resistance are reflected in the output voltage from the engine coolant temperature sensor.

The ECM monitors the sensor voltage and uses this value to calculate the engine coolant temperature. If the sensor output voltage deviates from the normal operating range, the ECM interprets this deviation as a malfunction in the engine coolant temperature sensor and stores the DTC.

Example:

Upon starting the engine, the engine coolant temperature is between 35°C and 60°C (95°F and 140°F). If after driving for 250 seconds, the engine coolant temperature remains within 3°C (5.4°F) of the starting temperature, the DTC is stored (2 trip detection logic).

INSPECTION PROCEDURE

Tech Tips


  • If DTC P0115, P0117 or P0118 is stored simultaneously with DTC P0116, the engine coolant temperature sensor may have an open or short circuit. Troubleshoot those DTCs first.

  • Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0116)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / DTC.

    5. Read the DTCs.

      Result
      Result Proceed to
      P0116 A
      P0116 and other DTCs B

    B

    GO TO DTC CHART Click here

    A

  2. INSPECT WATER INLET WITH THERMOSTAT


    1. Remove the water inlet with thermostat Click here.

    2. Measure the valve opening temperature of the thermostat.

      Standard value
      80 to 84°C (176 to 183°F)

      Tech Tips

      In addition to the above check, confirm that the valve is completely closed when the temperature is below the standard.


    NG

    REPLACE WATER INLET WITH THERMOSTAT Click here

    OK

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR Click here