DTC    P0115    Engine Coolant Temperature Circuit Malfunction

DTC    P0117    Engine Coolant Temperature Circuit Low Input

DTC    P0118    Engine Coolant Temperature Circuit High Input

for Preparation Click here


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.

HINT:
When any of DTCs P0115, P0117 and P0118 are set, the ECM enters fail-safe mode. During fail-safe mode, the engine coolant temperature is estimated to be 80°C (176°F) by the ECM. Fail-safe mode continues until a pass condition is detected.


DTC No.
DTC Detection Condition
Trouble Area
P0115
Open or short in engine coolant temperature sensor circuit for 0.5 seconds
(1-trip detection logic)
  1. Open or short in engine coolant temperature sensor circuit
  1. Engine coolant temperature sensor
  1. ECM
P0117
Short in engine coolant temperature sensor circuit for 0.5 seconds
(1-trip detection logic)
  1. Short in engine coolant temperature sensor circuit
  1. Engine coolant temperature sensor
  1. ECM
P0118
Open in engine coolant temperature sensor circuit for 0.5 seconds
(1-trip detection logic)
  1. Open in engine coolant temperature sensor circuit
  1. Engine coolant temperature sensor
  1. ECM

HINT:
When any of these DTCs are set, check the engine coolant temperature by entering the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.


Temperature Displayed
Malfunction
-40°C (-40°F)
Open circuit
140°C (284°F)
Short circuit

WIRING DIAGRAM


A148767E49


INSPECTION PROCEDURE

HINT:
Read freeze frame data using an intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.

1.READ VALUE USING INTELLIGENT TESTER (ENGINE COOLANT TEMPERATURE)

  1. Connect an intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the tester on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

  1. Read the value.

    Standard:
    Between 80°C and 100°C (176°F and 212°F) with warm engine.

    Result 
    Result
    		Proceed to
    -40°C (-40°F)
    		A
    140°C (284°F)
    		B
    Between 80°C and 100°C (176°F and 212°F)
    		C

    HINT:
    1. If there is an open circuit, the intelligent tester indicates -40°C (-40°F).
    1. If there is a short circuit, the intelligent tester indicates 140°C (284°F).



B
Go to step 4

C
CHECK FOR INTERMITTENT PROBLEMS (Click here)
A


2.READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN WIRE HARNESS)


    A107691E86

  1. Disconnect the engine coolant temperature sensor connector.

  1. Connect terminals 1 and 2 of the engine coolant temperature sensor connector on the wire harness side.

  1. Connect an intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the tester on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

  1. Read the value.

    Standard:
    140°C (284°F)

    Text in Illustration 
    *1
    		Engine Coolant Temperature Sensor
    *2
    		ECM
    *3
    		Front view of wire harness connector:
    (to Engine Coolant Temperature Sensor)

  1. Reconnect the engine coolant temperature sensor connector.



NG
Go to step 3
OK

CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE ENGINE COOLANT TEMPERATURE SENSOR (Click here)  

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


    A203950E01

  1. Disconnect the engine coolant temperature sensor connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    B38-2 - B8-66 (THW)
    		Always
    		Below 1 Ω
    B38-1 - B8-65 (ETHW)
    		Always
    		Below 1 Ω

    Text in Illustration 
    *1
    		Front view of wire harness connector:
    (to Engine Coolant Temperature Sensor)
    *2
    		Front view of wire harness connector:
    (to ECM)

  1. Reconnect the engine coolant temperature sensor connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM (Click here)  

4.READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS)


    A201300E04

  1. Disconnect the engine coolant temperature sensor connector.

  1. Connect an intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the tester on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

  1. Read the value.

    Standard:
    -40°C (-40°F)

    Text in Illustration 
    *1
    		Engine Coolant Temperature Sensor
    *2
    		ECM

  1. Reconnect the engine coolant temperature sensor connector.



NG
Go to step 5
OK

REPLACE ENGINE COOLANT TEMPERATURE SENSOR (Click here)  

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


    A203950E02

  1. Disconnect the engine coolant temperature sensor connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    B38-2 or B8-66 (THW) - Body ground
    		Always
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector:
    (to Engine Coolant Temperature Sensor)
    *2
    		Front view of wire harness connector:
    (to ECM)

  1. Reconnect the engine coolant temperature sensor connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ECM (Click here)