DTC P0115 Engine Coolant Temperature Circuit : DTC P0117 Engine Coolant Temperature Circuit Low Input : DTC P0118 Engine Coolant Temperature Circuit High Input: Wiring Diagram

Fig 1: Engine Coolant Temperature Circuit Diagram

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

• If other DTCs relating to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.
• 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.

1. READ OUTPUT DTC 
   1. Connect the intelligent tester to the DLC3.
   2. Turn the ignition switch ON.
   3. Turn the tester ON.
   4. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
   5. Read DTCs.
   DTC DISPLAY CHART
   
   

   Display (DTC Output)	Proceed To
   P0115	A
   P0117	B
   P0118	C

   B : GO TO STEP   5 

   C : GO TO STEP   3 

   A : Go to next step 

2. READ VALUE USING INTELLIGENT TESTER (ENGINE COOLANT TEMPERATURE) 
   1. Connect the intelligent tester to the DLC3.
   2. Turn the ignition switch ON.
   3. Turn the tester ON.
   4. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP.
   5. Read the value displayed on the tester.

   Standard temperature: 

   Between 80°C and 97°C (176°F and 207°F) with warm engine. 

   Result 

   RESULT CHART
   
   

   Temperature Displayed	Proceed To
   -40°C (-40°F)	A
   140°C (284°F) or higher	B
   Between 80°C and 97°C (176°F and 207°F)	C

   HINT:

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

   B : GO TO STEP   5 

   C : CHECK FOR INTERMITTENT PROBLEMS 

   A : Go to next step 

3. READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN WIRE HARNESS) 
   1. Disconnect the E2 Engine Coolant Temperature (ECT) sensor connector.
   2. Connect terminals 1 and 2 of the ECT sensor connector on the wire harness side.
   3. Connect the intelligent tester to the DLC3.
   4. Turn the ignition switch ON.
   5. Turn the tester ON.
   6. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP.
   7. Read the value displayed on the tester.

   Standard temperature: 

   140°C (284°F) or higher 

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

   Fig 2: Identifying E2 Engine Coolant Temperature Sensor Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG 

4. READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN ECM) 
   1. Disconnect the E2 ECT sensor connector.
   2. Connect terminals THW and E2 of the E8 ECM connector.

      HINT:

      Before checking, perform visual and contact pressure checks on the ECM connector.

   3. Connect the intelligent tester to the DLC3.
   4. Turn the ignition switch ON.
   5. Turn the tester ON.
   6. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP.
   7. Read the value displayed on the tester.

   Standard temperature: 

   140°C (284°F) or higher 

   OK : REPAIR OR REPLACE HARNESS AND CONNECTOR 

   Fig 3: Connecting Terminals THW And E2 Of E8 ECM Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

5. READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS) 
   1. Disconnect the E2 ECT sensor connector.
   2. Connect the intelligent tester to the DLC3.
   3. Turn the ignition switch ON.
   4. Turn the tester ON.
   5. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP.
   6. Read the value displayed on the tester.

   Standard: 

   -40°C (-40°F) 

   OK : REPLACE ENGINE COOLANT TEMPERATURE SENSOR 

   Fig 4: Checking For Short In Wire Harness Of E2 ECT Sensor

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG 

6. READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN ECM) 
   1. Disconnect the E8 ECM connector.
   2. Connect the intelligent tester to the DLC3.
   3. Turn the ignition switch ON.
   4. Turn the tester ON.
   5. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP.
   6. Read the value displayed on the tester.

      Standard: 

      -40°C (-40°F) 

   7. Reconnect the ECM connector.

   NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

   Fig 5: Disconnecting E8 ECM Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK : REPLACE ECM