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

1. Read the values using the Techstream (MAF).
   NOTE:

   • Turn the ignition switch off.
   • Perform the inspection with the vehicle indoors and on a level surface.
   • Perform the inspection of the mass air flow meter while it is installed in the air cleaner case (installed on the vehicle).
   • During the test, do not use the exhaust air duct to perform suction on the exhaust pipe.
2. Connect the Techstream to the DLC3.
3. Turn the ignition switch to ON (do not start the engine).
4. Turn the Techstream on.
5. Enter the following menus: Powertrain / Engine and ECT / Data List / MAF.
6. Wait for 30 seconds, and read the values on the Techstream.
   RESULT
   
   

   Result (gm/sec.)	Proceed to
   0.0	A
   More than 0.87	B
   Between 0.0 and 0.87	C

C → See step   8 

B → See step   6 

A: Go to next step 

Fig 1: Identifying Mass Air Flow Meter Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   B51-3 (+B) - Body ground	Ignition switch ON	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Mass Air Flow Meter)

NG → See step   5 

OK: Go to next step 

Fig 2: Identifying ECM Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Start the engine.
2. Measure the voltage between the terminals of the ECM connector.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   B48-14 (VG) - B48-13 (E2G)	Engine idling	0.5 to 3.0 V

   TEXT IN ILLUSTRATION
   
   

   *1	Component with harness connected (ECM)

NG → See step   4 

OK → See step   10 

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

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   B51-5 (VG) - B48-14 (VG)	Always	Below 1 Ω
   B51-4 (E2G) - B48-13 (E2G)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   B51-5 (VG) or B48-14 (VG) - Body ground	Always	10 kΩ or higher
   B51-4 (E2G) or B48-13 (E2G) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   11 

1. Disconnect the MAF meter connector.
2. Remove the EFI relay from the engine room relay block.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   B51-3 (+B) - 3 (EFI relay)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   B51-3 (+B) or 3 (EFI relay) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   13 

Fig 3: Identifying ECM Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   B48-13 (E2G) - Body ground	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *1	Component with harness connected (ECM)

NG → See step   12 

OK: Go to next step 

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

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   B51-4 (E2G) - B48-13 (E2G)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   B51-4 (E2G) or B48-13 (E2G) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   9