Dtc P0115 Engine Coolant Temperature Circuit

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING INTELLIGENT TESTER (ENGINE COOLANT TEMPERATURE)

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

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

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

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

REPLACE ECM

CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE ENGINE COOLANT TEMPERATURE SENSOR.

REPAIR OR REPLACE HARNESS OR CONNECTOR

CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM.

REPLACE ENGINE COOLANT TEMPERATURE SENSOR

CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

DESCRIPTION

HINT:

If DTC P0115, P0117 or P0118 is stored, the ECM operates the fail-safe function in which the engine coolant temperature is assumed to be 80°C (176°F).

HINT:

1. If DTC P0115, P0117 and/or P0118 is stored, the following symptoms may appear:
   
1. Misfire
   
2. Combustion noise
   
3. Black smoke
   
4. White smoke
   
5. Lack of power
   
2. When DTC P0115, P0117 and/or P0118 is stored, check the engine coolant temperature by entering the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
   
   

   Reference

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

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

After replacing the ECM, the new ECM needs registration (HILUX_TGN26 RM0000012XK071X.html) and initialization (HILUX_TGN26 RM000000TIN04FX.html).

HINT:

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, and other data from the time the malfunction occurred.

1. Connect the intelligent tester to the DLC3.
   

2. Turn the ignition switch to ON and turn the tester on.
   

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

4. Read the value.
   

   OK:

   70 to 90°C (158 to 194°F) with warm engine
   

   
   

   Result

   Result	Proceed to
   -40°C (-40°F)	A
   140°C (284°F) or higher	B
   70 to 90°C (158 to 194°F)	C

   HINT:

   1. If there is an open circuit, the tester indicates -40°C (-40°F).
      
   2. If there is a short circuit, the tester indicates 140°C (284°F) or higher.
      

1. Disconnect the engine coolant temperature sensor connector.
   

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

3. Connect the intelligent tester to the DLC3.
   

4. Turn the ignition switch to ON and turn the tester on.
   

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

6. Read the value.
   

   OK:

   140°C (284°F) or higher
   

   Text in Illustration

   *1	Engine Coolant Temperature Sensor
   *2	ECM
   *a	Front view of wire harness connector (to Engine Coolant Temperature Sensor)

7. Reconnect the engine coolant temperature sensor connector.
   

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
   C17-2 - C22-19 (THW)	Always	Below 1 Ω
   C17-1 - C22-28 (E2)	Always	Below 1 Ω

4. Reconnect the engine coolant temperature sensor connector.
   

5. Reconnect the ECM connector.
   

1. Disconnect the engine coolant temperature sensor connector.
   

2. Connect the intelligent tester to the DLC3.
   

3. Turn the ignition switch to ON and turn the tester on.
   

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

5. Read the value.
   

   OK:

   -40°C (-40°F)
   

   Text in Illustration

   *1	Engine Coolant Temperature Sensor
   *2	ECM

6. Reconnect the engine coolant temperature sensor connector.
   

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
   C17-2 or C22-19 (THW) - Body ground	Always	10 kΩ or higher

4. Reconnect the engine coolant temperature sensor connector.
   

5. Reconnect the ECM connector.
   

1. Replace the ECM (HILUX_TGN26 RM0000013Z001HX.html).
   

1. Replace the engine coolant temperature sensor (HILUX_TGN26 RM0000013ZA01PX.html).
   

1. Repair or replace the harness or connector.
   

1. Replace the ECM (HILUX_TGN26 RM0000013Z001HX.html).
   

1. Replace the engine coolant temperature sensor (HILUX_TGN26 RM0000013ZA01PX.html).
   

1. Connect the intelligent tester to the DLC3.
   

2. Clear the DTCs (HILUX_TGN26 RM000000PDK120X.html).
   

3. Turn the ignition switch to ON for 1 second.
   

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

5. Confirm that the DTC is not output again.