Inspection Procedure

WARNING: This page is about a different variant/trim than selected.

HINT:

Read freeze frame data using the Techstream. 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.

READ VALUE USING TECHSTREAM (ENGINE COOLANT TEMPERATURE)

Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
Read the value displayed on the Techstream.
Standard Value:

Between 80°C and 100°C (167 F and 212°F) with a warm engine .

Result

RESULT REFERENCE

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:

If there is an open circuit, the Techstream indicates 40°C (-40°F).
If there is a short circuit, the Techstream indicates 140°C (284°F).

B: Go to step 4

C: CHECK FOR INTERMITTENT PROBLEMS (See CHECK FOR INTERMITTENT PROBLEMS )

A: Go to Next Step

READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS)
1. Disconnect the engine coolant temperature sensor connector.
2. Connect terminals 1 and 2 of the engine coolant temperature sensor connector on the wire harness side.
3. Connect the Techstream to the DLC3.
4. Turn the ignition switch to ON.
5. Turn the Techstream on.
6. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
7. Read the value displayed on the Techstream.
8. Reconnect the engine coolant temperature sensor connector.
NG: Go to step 3

Fig 1: Engine Coolant Temperature Sensor And ECM - Circuit Diagram
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: REPLACE ENGINE COOLANT TEMPERATURE SENSOR (See ENGINE COOLANT TEMPERATURE SENSOR )

CHECK HARNESS AND CONNECTOR (ENGINE COOLANT TEMPERATURE SENSOR ECM)

Disconnect the engine coolant temperature sensor connector.
Disconnect the ECM connector.

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

Standard Resistance

RESISTANCE REFERENCE

Tester Connection	Condition	Specified Condition
B3-2 - B29-97 (THW)	Always	Below 1 Ω
B3-1 - B29-96 (ETHW)	Always	Below 1 Ω

Reconnect the engine coolant temperature sensor connector.
Reconnect the ECM connector.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE COOLANT TEMPERATURE SENSOR - ECM)

Fig 2: Identifying Engine Coolant Temperature Sensor Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: REPLACE ECM (See ECM )

READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS)
1. Disconnect the engine coolant temperature sensor connector.
2. Connect the Techstream to the DLC3.
3. Turn the ignition switch to ON.
4. Turn the Techstream on.
5. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.
6. Read the value displayed on the Techstream.
  Standard Value:
  
  -40°C (-40°F)
7. Reconnect the engine coolant temperature sensor connector.
Fig 3: Engine Coolant Temperature Sensor And ECM - Circuit Diagram
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 5

OK: REPLACE ENGINE COOLANT TEMPERATURE SENSOR (See ENGINE COOLANT TEMPERATURE SENSOR )