1Vd-Ftv Engine Control. Dtc P0102 Mass Or Volume Air Flow Circuit Low Input

Engine Hybrid System. Land Cruiser. Urj200, 202 Grj200 Vdj200

1Vd-Ftv Engine Control. Land Cruiser. Urj200, 202 Grj200 Vdj200

DESCRIPTION

INSPECT MASS AIR FLOW METER (POWER SOURCE VOLTAGE)

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

INSPECT MASS AIR FLOW METER

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - INTEGRATION RELAY)

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

CHECK HARNESS AND CONNECTOR (SENSOR GROUND)

DTC P0102 Mass or Volume Air Flow Circuit Low Input

DTC P0103 Mass or Volume Air Flow Circuit High Input

DESCRIPTION

The Mass Air Flow (MAF) meter is a sensor that measures the amount of air flowing through the throttle valve.
The ECM uses this information to determine the fuel injection time and to provide the appropriate air-fuel ratio.
Inside the MAF meter, there is a heated platinum wire which is exposed to the flow of intake air.
By applying a specific electrical current to the wire, the ECM heats it to a given temperature. The flow of incoming air cools both the wire and an internal thermistor, affecting their resistance. To maintain a constant current value, the ECM varies the voltage applied to the wire and internal thermistor. The voltage level is proportional to the airflow through the sensor, and the ECM uses it to calculate the intake air volume.
The circuit is constructed so that the platinum hot wire and the cold film element create a bridge circuit, and the power transistor is controlled so that the potentials of A and B remain equal to maintain the predetermined temperature.

HINT:

When any of these DTCs are set, the ECM enters fail-safe mode. During fail-safe mode, the ignition timing is calculated by the ECM, according to the engine RPM and throttle valve position. Fail-safe mode continues until a pass condition is detected.

Land Cruiser. Urj200, 202 Grj200 Vdj200.1Vd-Ftv Engine Control.Ecd System (W/ Dpf).
Dtc
P0102 Mass Or Volume Air Flow Circuit Low Input

P0102
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Ignition switch ON for 3 seconds	MAF meter voltage is 0.2 V or less with the engine speed at 4000 rpm or less for 3 seconds (1 trip detection logic).	Open in Mass Air Flow (MAF) meter circuit Mass air flow meter ECM

P0103
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Ignition switch ON for 3 seconds	MAF meter voltage is 4.9 V or more with the engine speed at 4000 rpm or less for 3 seconds (1 trip detection logic).	Shot in Mass Air Flow (MAF) meter circuit Mass air flow meter ECM

Related Data List
DTC No.	Data List
P0102	MAF
P0103	MAF

HINT:

If DTC P0102 or P0103 is stored, the following symptoms may appear (as the ECU mistakenly determines that there is less air than the actual intake air amount, EGR is decreased to match the target EGR):

Combustion noise worsens

If DTC P0102 or P0103 is stored, the following symptoms may appear (as the ECU mistakenly determines that there is more air than the actual intake air amount, EGR is increased to match the target EGR):

Misfire
White smoke
Black smoke

After confirming DTC P0102 or P0103, check the mass air flow ratio by entering the following menus: Powertrain / Engine and ECT / Data List / MAF.
Mass Air Flow Rate (gm/sec)
Malfunction
Approximately 0.0
Open in Mass Air Flow (MAF) meter power source circuit
Open or short in VG circuit
174.0 or more
Open in E2G circuit

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 at 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.

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT:

Read freeze frame data using the GTS. 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 DTC OUTPUT

Connect the GTS to the DLC3.

Turn the ignition switch to ON.

Turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

Read DTCs.

Result
Result
Proceed to
DTC P0102 is output
A
DTC P0103 is output
B

Result
Result	Proceed to
DTC P0102 is output	A
DTC P0103 is output	B

Go to step 6

A

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

Disconnect the MAF meter connector.

Turn the ignition switch to ON.

Measure the voltage according to the value(s) in the table below.
Standard voltage:
Tester Connection
Switch Condition
Specified Condition
C50-1 (+B) - Body ground
Ignition switch ON
11 to 14 V

Go to step 5

OK

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

Disconnect the MAF meter connector.

Disconnect the ECM connector.

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

Standard Resistance:

for LHD
Tester Connection
Condition
Specified Condition
C50-3 (VG) - C45-119 (VG)
Always
Below 1 Ω
C50-2 (E2G) - C45-94 (EVG)
Always
Below 1 Ω
C50-3 (VG) or C45-119 (VG) - Body ground
Always
10 kΩ or higher

for RHD
Tester Connection
Condition
Specified Condition
C50-3 (VG) - C46-119 (VG)
Always
Below 1 Ω
C50-2 (E2G) - C46-94 (EVG)
Always
Below 1 Ω
C50-3 (VG) or C46-119 (VG) - Body ground
Always
10 kΩ or higher

for LHD
Tester Connection	Condition	Specified Condition
C50-3 (VG) - C45-119 (VG)	Always	Below 1 Ω
C50-2 (E2G) - C45-94 (EVG)	Always	Below 1 Ω
C50-3 (VG) or C45-119 (VG) - Body ground	Always	10 kΩ or higher

for RHD
Tester Connection	Condition	Specified Condition
C50-3 (VG) - C46-119 (VG)	Always	Below 1 Ω
C50-2 (E2G) - C46-94 (EVG)	Always	Below 1 Ω
C50-3 (VG) or C46-119 (VG) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

4.INSPECT MASS AIR FLOW METER

Inspect the mass air flow meter, referring to the On-vehicle inspection for mass air flow meter (Click here).

Inspect the mass air flow meter, referring to the inspection for mass air flow meter (Click here).

Inspect the function of the mass air flow meter.
1. Connect the GTS to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the GTS on.
4. Enter the following menus: Powertrain / Engine and ECT / Data List / MAF.
5. start the engine.
6. Check that the MAF value changes when the engine is raced.
  OK:
  The reading changes.

REPLACE MASS AIR FLOW METER (Click here)

REPLACE ECM (Click here)

5.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - INTEGRATION RELAY)

Disconnect the MAF meter connector.

Remove the integration relay from the engine room relay block.

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

Standard resistance:

Tester Connection
Condition
Specified Condition
C50-1 (+B) - 1S-7
Always
Below 1 Ω
C50-1 (+B) or 1S-7 - Body ground
Always
10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

CHECK ECM POWER SOURCE CIRCUIT (Click here)

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

Disconnect the MAF meter connector.

Disconnect the ECM connector.

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

Standard Resistance:

for LHD
Tester Connection
Condition
Specified Condition
C50-3 (VG) - C45-119 (VG)
Always
Below 1 Ω
C50-2 (E2G) - C45-94 (EVG)
Always
Below 1 Ω
C50-3 (VG) or C45-119 (VG) - Body ground
Always
10 kΩ or higher

for RHD
Tester Connection
Condition
Specified Condition
C50-3 (VG) - C46-119 (VG)
Always
Below 1 Ω
C50-2 (E2G) - C46-94 (EVG)
Always
Below 1 Ω
C50-3 (VG) or C46-119 (VG) - Body ground
Always
10 kΩ or higher

for LHD
Tester Connection	Condition	Specified Condition
C50-3 (VG) - C45-119 (VG)	Always	Below 1 Ω
C50-2 (E2G) - C45-94 (EVG)	Always	Below 1 Ω
C50-3 (VG) or C45-119 (VG) - Body ground	Always	10 kΩ or higher

for RHD
Tester Connection	Condition	Specified Condition
C50-3 (VG) - C46-119 (VG)	Always	Below 1 Ω
C50-2 (E2G) - C46-94 (EVG)	Always	Below 1 Ω
C50-3 (VG) or C46-119 (VG) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

7.CHECK HARNESS AND CONNECTOR (SENSOR GROUND)

Disconnect the MAF meter connector.

Measure the resistance according to the value(s) in the table below.
Standard resistance:
Tester Connection
Condition
Specified Condition
C50-2 (E2G) - Body ground
Always
Below 1 Ω

REPLACE ECM (Click here)

REPLACE MASS AIR FLOW METER (Click here)

Mass Air Flow Rate (gm/sec)	Malfunction
Approximately 0.0	Open in Mass Air Flow (MAF) meter power source circuit Open or short in VG circuit
174.0 or more	Open in E2G circuit

Tester Connection	Switch Condition	Specified Condition
C50-1 (+B) - Body ground	Ignition switch ON	11 to 14 V