Inspection Procedure

WARNING: This page is about a different car, the 2007 Toyota Tacoma. However, it is still accessible from the selected car via links, so may be relevant.

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. Freeze frame data record 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.

READ DATA LIST (ENGINE COOLANT TEMPERATURE)

Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the intelligent tester ON.
Select the following menus items: DIAGNOSIS / ENHANCED OBD II / DATA LIST /PRIMARY / COOLANT TEMP.

Read the value displayed on the tester.

Standard:

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

Result

RESULT REFERENCE CHART

Temperature Displayed	Proceed to
-40°C (-40°F)	A
140°C (284°F)	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).

B: Go to step 4

C : CHECK FOR INTERMITTENT PROBLEMS

A: Go to Next Step

READ DATA LIST (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 to ON and turn the intelligent tester ON.
5. Select the following menus items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / COOLANT TEMP.
6. Read the value displayed on the tester.
  Standard :
  
  140°C (284°F)
7. Reconnect the ECT sensor connector.
OK : CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE ENGINE COOLANT TEMPERATURE SENSOR

NG: Go to Next Step
READ DATA LIST (CHECK FOR OPEN IN ECM)
1. Disconnect the E2 ECT sensor connector.
2. Connect terminals THW of the E2 of the ECM connector.
  HINT:
  
  Before checking, do a visual and contact pressure check for the ECM connector.
3. Connect the intelligent tester to the DLC3.
4. Turn the ignition switch to ON and turn the intelligent tester ON.
5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / COOLANT TEMP.
6. Read the value displayed on the tester.
  Standard:
  
  140°C (284°F)
7. Reconnect the ECT sensor connector.
NG: CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM

OK : REPAIR OR REPLACE HARNESS OR CONNECTOR
READ DATA LIST (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 to ON and turn the intelligent tester ON.
4. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / COOLANT TEMP.
5. Read the value displayed on the tester.
  Standard:
  
  -40°C (-40°F)
6. Reconnect the ECT sensor connector.
  
  Fig 3: Identifying ECT Sensor And ECM
  Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK : REPLACE ENGINE COOLANT TEMPERATURE SENSOR

NG: Go to Next Step
READ DATA LIST (CHECK FOR SHORT IN ECM)
1. Disconnect the E4 ECM sensor connector.
2. Connect the intelligent tester to the DLC3.
3. Turn the ignition switch to ON and turn the intelligent tester ON.
4. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / COOLANT TEMP.
5. Read the value displayed on the tester.
  Standard:
  
  -40°C (-40°F)
6. Reconnect the ECM sensor connector.
NG: REPLACE ECM

OK : REPAIR OR REPLACE HARNESS OR CONNECTOR