Toyota Tundra. Manual — part 1527

Fig. 74: Intake Air Temperature Sensor - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

HINT:

Read freeze frame data using the Techstream. 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 VALUE USING TECHSTREAM (INTAKE AIR TEMPERATURE)

a. Connect the Techstream to the DLC3.

b. Turn the ignition switch to ON.

c. Turn the Techstream ON.

d. Enter the following menus: Powertrain/Engine and ECT/All Data/Intake Air.

e. Read the value displayed on the Techstream.

Standard:

Same as actual Intake Air Temperature (IAT).

Result

RESULT REFERENCE

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

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) or higher.

B: Go to step 4

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

A: Go to next step.

2. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS)

a. Disconnect the D7 MAF meter connector.

Fig. 75: Identifying Terminals Of D7 MAF Meter Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

b. Connect terminals 4 (THA) and 5 (E2) of the MAF meter wire harness side connector.

c. Connect the Techstream to the DLC3.

d. Turn the ignition switch to ON.

e. Turn the Techstream ON.

f. Enter the following menus: Powertrain/Engine and ECT/All Data/Intake Air.

g. Read the value displayed on the Techstream.

Temperature Displayed Proceed to
-40°C (-40°F)

A

140°C (284°F) or higher

B

Same as actual IAT

C

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

Standard value: 140°C (284°F) or higher

NG: Go to step 3

OK: CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE MASS AIR
FLOW METER (See REMOVAL )

3. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)

a. Disconnect the D7 MAF meter connector.

Fig. 76: Identifying Terminals Of D7 MAF And D74 ECM Meter Connectors
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

b. Disconnect the D74 ECM connector.

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

Standard resistance

RESISTANCE SPECIFIED CONDITION

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM (See
REMOVAL )

4. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS)

a. Disconnect the D7 MAF meter connector.

Tester Connection

Condition Specified Condition

D7-4 (THA) - D74-73 (THA) Always

Below 1 ohms

D7-5 (E2) - D74-97 (ETHW)

Always

Below 1 ohms

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

Fig. 77: Identifying D7 MAF Meter Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

b. Connect the Techstream to the DLC3.

c. Turn the ignition switch to ON.

d. Turn the Techstream ON.

e. Enter the following menus: Powertrain/Engine and ECT/All Data/Intake Air.

f. Read the value displayed on the Techstream.

Standard value: -40°C (-40°F)

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra