Toyota Tundra. Manual — part 1163

MONITOR DESCRIPTION

If there is a defect in the MAF meter or an open or short circuit, the voltage level deviates from the normal
operating range. The ECM interprets this deviation as a malfunction in the MAF meter and sets a DTC.

Example:

When the sensor output voltage remains less than 0.2 V, or more than 4.9 V, for more than 3 seconds, the ECM
sets a DTC.

If the malfunction is not repaired successfully, a DTC is set 3 seconds after the engine is next started.

MONITOR STRATEGY

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

P0102:

TYPICAL MALFUNCTION THRESHOLDS

P0103:

TYPICAL MALFUNCTION THRESHOLDS

Approximately 0.0



Open in Mass Air Flow (MAF) meter power source circuit



Open or short in VG circuit

271.0 or more



Open in EVG circuit

Related DTCs

P0102: MAF meter range check (Low voltage)
P0103: MAF meter range check (High voltage)

Required Sensors/Components (Main)

MAF meter

Required Sensors/Components (Related)

Crankshaft position sensor

Frequency of Operation

Continuous

Duration

3 seconds

MIL Operation

Immediate: Engine RPM less than 4000 RPM
2 driving cycles: Engine RPM 4000 RPM or more

Sequence of Operation

None

Monitor runs whenever following DTCs not present

None

MAF meter voltage

Less than 0.2 V

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

COMPONENT OPERATING RANGE

COMPONENT OPERATING RANGE

WIRING DIAGRAM

Fig. 55: Mass Or Volume Air Flow Wiring Diagram

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 (MASS AIR FLOW RATE)

a. Connect the Techstream to the DLC3.

b. Start the engine.

c. Turn the Techstream ON.

d. Enter the following menus: Powertrain/Engine and ECT/Data List/All Data/MAF.

e. Read the values displayed on the Techstream.

Result

RESULT CHART

MAF meter voltage

More than 4.9 V

MAF meter voltage

Between 0.4 V and 2.2 V

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

B : Go to step 6

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

A : Go to next step

2. INSPECT MASS AIR FLOW METER (POWER SOURCE VOLTAGE)

a. Disconnect the D8 Mass Air Flow (MAF) meter connector.

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

Standard voltage

TESTER CONNECTION SPECIFIED CONDITION

NG : Go to step 5

Fig. 56: Identifying D8 Mass Air Flow Meter Connector Terminals

OK : Go to next step

3. INSPECT MASS AIR FLOW METER

a. Inspect mass air flow meter (See INSPECTION ).

NG : REPLACE MASS AIR FLOW METER (See REMOVAL )

OK : Go to next step

Mass Air Flow Rate (g/sec.)

Proceed To

0.0

A

271.0 or more

B

Between 1.0 and 270.0*

C

HINT:
*: The value must change when the throttle valve is open or closed with the engine running.

Tester Connection

Switch Condition Specified Condition

D8-1 (+B) - Body ground Ignition switch ON

11 to 14 V

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

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

a. Disconnect the D8 MAF meter connector.

b. Disconnect the D74 ECM connector.

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

Standard resistance (Check for open)

TESTER CONNECTION SPECIFIED CONDITION

Standard resistance (Check for short)

TESTER CONNECTION SPECIFIED CONDITION

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig. 57: Identifying D8 MAF Meter & D74 Connector Terminals

OK : REPLACE ECM (See REMOVAL )

Tester Connection

Condition Specified Condition

D8-3 (VG) - D74-74 (VG)

Always

Below 1 ohms

D8-2 (E2G) - 074-75 (E2G) Always

Below 1 ohms

Tester Connection

Condition Specified Condition

D8-3 (VG) or D74-74 (VG) - Body ground

Always

10 kohms or higher

D8-2 (E2G) or D74-75 (E2G) - Body ground Always

10 kohms or higher

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra