Inspection Procedure

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 an intelligent tester or OBD II scan tool. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

1. READ VALUE OF INTELLIGENT TESTER OR OBD II SCAN TOOL (ENGINE COOLANT TEMPERATURE) 
   1. Connect an intelligent tester or OBD II scan tool to the DLC3.
   2. Turn the ignition switch to ON.
   3. Turn the tester or scan tool 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.
   6. If using an OBD II scan tool, refer to the instruction manual.

      Standard: 

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

      Result 

      DTC RESULT DESCRIPTION
      
      

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

   B: Go to step  4

   C: CHECK FOR INTERMITTENT PROBLEMS 

   A: Go to Next Step 

2. READ VALUE OF INTELLIGENT TESTER OR OBD II SCAN TOOL (CHECK FOR OPEN IN WIRE HARNESS) 
   Fig 1: Checking Open In Wire Harness

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Confirm connector connecting condition.
   2. Disconnect the E2 Engine Coolant Temperature (ECT) sensor connector.
   3. Connect terminals 1 and 2 of the ECT sensor connector on the wire harness side.
   4. Connect the intelligent tester or OBD II scan tool to the DLC3.
   5. Turn the ignition switch to ON.
   6. Turn the tester or scan tool ON.
   7. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP.
   8. Read the value displayed on the tester.
   9. If using an OBD II scan tool, refer to the instruction manual.

      Standard: 

      140°C (284°F) or higher 

   10. Reconnect the ECT sensor connector.

   OK : REPLACE ENGINE COOLANT TEMPERATURE SENSOR 

   NG: Go to Next Step 

3. READ VALUE OF INTELLIGENT TESTER OR OBD II SCAN TOOL (CHECK FOR OPEN IN ECM) 
   1. Disconnect the E2 ECT sensor connector.
   2. Connect terminals THW and E2 of the E3 ECM connector.

      HINT:

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

   3. Connect the intelligent tester or OBD II scan tool to the DLC3.
   4. Turn the ignition switch to ON.
   5. Turn the tester or scan tool ON.
   6. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP.
      Fig 2: Checking Open In ECM

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   7. Read the value displayed on the tester.
   8. If using an OBD II scan tool, refer to the instruction manual.

      Standard: 

      140°C (284°F) or higher 

   9. Reconnect the ECT sensor connector.

   OK : REPAIR OR REPLACE HARNESS OR CONNECTOR 

   NG: REPLACE ECM 

4. READ VALUE OF INTELLIGENT TESTER OR OBD II SCAN TOOL (CHECK FOR SHORT IN WIRE HARNESS) 
   1. Disconnect the E2 ECT sensor connector.
   2. Connect the intelligent tester or OBD II scan tool to the DLC3.
   3. Turn the ignition switch to ON.
   4. Turn the tester or scan tool 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.
   7. If using an OBD II scan tool, refer to the instruction manual.
      Fig 3: Checking Short In Wire Harness

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      -40°C (-40°F) 

   8. Reconnect the ECT sensor connector.

   OK : REPLACE ENGINE COOLANT TEMPERATURE SENSOR 

   NG: Go to Next Step 

5. READ VALUE OF INTELLIGENT TESTER OR OBD II SCAN TOOL (CHECK FOR SHORT IN ECM) 
   Fig 4: Checking Short In ECM

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Disconnect the E3 ECM connector.
   2. Connect the intelligent tester or OBD II scan tool to the DLC3.
   3. Turn the ignition switch to ON.
   4. Turn the tester or scan tool 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.
   7. If using an OBD II scan tool, refer to the instruction manual.

      Standard: 

      -40°C (-40°F) 

   8. Reconnect the ECM connector.

   OK : REPAIR OR REPLACE HARNESS OR CONNECTOR 

   NG: REPLACE ECM