DTC P0102: Mass or Volume Air Flow Circuit Low Input; DTC P0103: Mass or Volume Air Flow Circuit High Input: Procedure

1. Connect the Techstream to the DLC3.
2. Start the engine.
3. Turn the Techstream on.
4. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / MAF.
5. Read the values displayed on the Techstream.
   RESULT
   
   

   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.

C → See step   5 

B → See step   10 

A: Go to next step 

Fig 1: Identifying C3 Mass Air Flow Meter Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the C3 Mass Air Flow (MAF) meter connector.
2. Turn the engine switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   C3-1 (+B) - Body ground	Engine switch on (IG)	11 to 14 V

NG → See step   8 

OK: Go to next step 

1. Disconnect the MAF meter connector.
   Fig 2: Identifying MAF Meter

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Connect the Techstream to the DLC3.
3. Turn the engine switch on (IG).
4. Turn the Techstream on.
5. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / MAF.
6. Check the MAF value when air is blown to the mass air flow meter, as shown in the illustration.

   OK

   The MAF value changes.

NG → See step   6 

OK: Go to next step 

Fig 3: Identifying C3 MAF Meter And C53 ECM Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the C3 MAF meter connector.
2. Disconnect the C53 ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C3-3 (VG) - C53-74 (VG)	Always	Below 1 Ω
   C3-2 (E2G) - C53-75 (E2G)	Always	Below 1 Ω
   C3-3 (VG) or C53-74 (VG) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   7 

1. Check the EFI NO. 2 fuse.
   1. Remove the EFI NO. 2 fuse from the engine room relay block.
   2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection	Condition	Specified Condition
      EFI NO. 2 fuse	Always	Below 1 Ω

   3. Reinstall the EFI NO. 2 fuse.
   Fig 4: Identifying Mass Air Flow Meter And Integration Relay Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the C3 MAF meter connector.
3. Remove the integration relay from the engine room relay block.
4. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C3-1 (+B) - 1B-4	Always	Below 1 Ω
   C3-1 (+B) or 1B-4 - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   9 

Fig 5: Identifying C3 MAF Meter And C53 ECM Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the C3 MAF meter connector.
2. Disconnect the C53 ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C3-3 (VG) - C53-74 (VG)	Always	Below 1 Ω
   C3-2 (E2G) - C53-75 (E2G)	Always	Below 1 Ω
   C3-3 (VG) or C53-74 (VG) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

Fig 6: Identifying C3 MAF Meter Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the C3 MAF meter connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C3-2 (E2G) - Body ground	Always	Below 1 Ω

NG → See step   13 

OK → See step   12