Dtc P0100 Mass Or Volume Air Flow Circuit

Engine. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35
1Az-Fe Engine Control System. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING INTELLIGENT TESTER (MASS AIR FLOW RATE)

CHECK MASS AIR FLOW METER (POWER SOURCE VOLTAGE)

INSPECT MASS AIR FLOW METER

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

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

CHECK HARNESS AND CONNECTOR (SENSOR GROUND)

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

DTC P0100 Mass or Volume Air Flow Circuit

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 temperature sensor 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.

Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.1Az-Fe Engine Control System.Sfi System. Dtc P0100 Mass Or Volume Air Flow Circuit


DTC No.
DTC Detection Condition
Trouble Area
P0100
MAF meter voltage less than 0.2 V, or more than 4.9 V for 3 seconds
(1 trip detection logic)
  1. Open or short in MAF meter circuit
  2. MAF meter
  3. ECM
P0102
MAF meter voltage less than 0.2 V for 3 seconds
(1 trip detection logic)
  1. Open or short in MAF meter circuit
  2. MAF meter
  3. ECM
P0103
MAF meter voltage more than 4.9 V for 3 seconds
(1 trip detection logic)
  1. Open or short in MAF meter circuit
  2. MAF meter
  3. ECM

HINT:
When any of these DTCs are set, check the air-flow rate by selecting the following menu items on the intelligent tester: Powertrain / Engine and ECT / Data List / MAF.

Mass Air Flow Rate (gm/s)
Malfunction
Approximately 0.0
  1. Open in Mass Air Flow (MAF) meter power source circuit
  2. Open or short in VG circuit
271.0 or more
  1. Open in E2G circuit

WIRING DIAGRAM


Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.1Az-Fe Engine Control System.Sfi System. Dtc P0100 Mass Or Volume Air Flow Circuit


INSPECTION PROCEDURE

HINT:
Read freeze frame data using the intelligent tester. 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 INTELLIGENT TESTER (MASS AIR FLOW RATE)

  1. Connect the intelligent tester to the DLC3.

  1. Start the engine and turn the tester on.

  1. Select the following menu items: Powertrain / Engine and ECT / Data List / MAF.

  1. Read the values displayed on the tester.

    Result:
    Mass Air Flow Rate (gm/s)
    		Proceed to
    0.0
    		A
    271.0 or more
    		B
    Between 1.0 and 270.0 (*1)
    		C
    *1: The value must change when the throttle valve is open or closed with the engine running.


B
Go to step 6

C
CHECK FOR INTERMITTENT PROBLEMS (RAV4_ACA30 RM000000PDQ0AIX.html)
A


2.CHECK MASS AIR FLOW METER (POWER SOURCE VOLTAGE)
Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.1Az-Fe Engine Control System.Sfi System. Dtc P0100 Mass Or Volume Air Flow Circuit

  1. Disconnect the Mass Air Flow (MAF) meter connector.

  1. Turn the ignition switch on (IG).

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

    Standard voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    B1-3 (+B) - Body ground
    		Ignition switch ON
    		11 to 14 V
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Mass Air Flow Meter)

  1. Reconnect the MAF meter connector.



NG
Go to step 5
OK


3.INSPECT MASS AIR FLOW METER
Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35

  1. Perform On-vehicle Inspection (RAV4_ACA30 RM000001RYE012X.html).

  1. Inspect the function of the mass air flow meter.

    1. Remove the mass air flow meter with the connector connected.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the ignition switch on (IG).

    4. Turn the tester on.

    5. Enter the following menus: Powertrain / Engine / Data List / MAF.

    6. Blow air to the mass air flow meter and check that the intake air amount reading changes.

      OK:
      The reading changes.


NG
REPLACE MASS AIR FLOW METER
OK


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

  1. Disconnect the MAF meter connector.

  1. Disconnect the ECM connector.

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

    Standard resistance (Check for open):
    Tester Connection
    		Condition
    		Specified Condition
    B1-5 (VG) - B32-118 (VG)
    		Always
    		Below 1 Ω
    B1-4 (E2G) - B32-116 (E2G)
    		Always
    		Below 1 Ω
    Standard resistance (Check for short):
    Tester Connection
    		Condition
    		Specified Condition
    B1-5 (VG) or B32-118 (VG) - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the MAF meter connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ECM (RAV4_ACA30 RM0000017UO01FX.html)

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

  1. Disconnect the MAF meter connector.

  1. Remove the integration relay from the engine room No. 1 relay block.

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

    Standard resistance (Check for open):
    Tester Connection
    		Condition
    		Specified Condition
    B1-3 (+B) - 1A-4
    		Always
    		Below 1 Ω
    Standard resistance (Check for short):
    Tester Connection
    		Condition
    		Specified Condition
    B1-3 (+B) or 1A-4 - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the MAF meter connector.

  1. Reinstall the integration relay.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

CHECK ECM POWER SOURCE CIRCUIT (RAV4_ACA30 RM000001DN802SX.html)

6.CHECK HARNESS AND CONNECTOR (SENSOR GROUND)

  1. Disconnect the MAF meter connector.

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

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    B1-4 (E2G) - Body ground
    		Always
    		Below 1 Ω

  1. Reconnect the MAF meter connector.



OK
REPLACE MASS AIR FLOW METER (RAV4_ACA30 RM0000017TY00UX.html)
NG


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

  1. Disconnect the MAF meter connector.

  1. Disconnect the ECM connector.

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

    Standard resistance (Check for open):
    Tester Connection
    		Condition
    		Specified Condition
    B1-5 (VG) - B32-118 (VG)
    		Always
    		Below 1 Ω
    B1-4 (E2G) - B32-116 (E2G)
    		Always
    		Below 1 Ω
    Standard resistance (Check for short):
    Tester Connection
    		Condition
    		Specified Condition
    B1-5 (VG) or B32-118 (VG) - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the MAF meter connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ECM (RAV4_ACA30 RM0000017UO01FX.html)