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. Turn the engine switch on (IG).
3. Turn the Techstream on.
4. Enter the following menus: Powertrain / Engine / Trouble Codes.
5. Read the DTCs.

   Result

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

B → See step   5 

A: Go to next step 

1. Disconnect the mass air flow meter sub-assembly connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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
   D3-3 (+B) - Body ground	Engine switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Mass Air Flow Meter Sub-assembly)

4. Reconnect the mass air flow meter sub-assembly connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - EFI MAIN RELAY) 

OK: Go to next step 

1. Disconnect the mass air flow meter sub-assembly 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
   D3-5 (VG) - D1-74 (VG)	Always	Below 1 Ω
   D3-4 (E2G) - D1-75 (E2G)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   D3-5 (VG) or D1-74 (VG) - Body ground	Always	10 kΩ or higher

4. Reconnect the mass air flow meter sub-assembly connector.
5. Reconnect the ECM connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM) 

OK: Go to next step 

1. Perform On-vehicle Inspection. Refer to ON-VEHICLE INSPECTION [03/2012 - ] .
2. Perform Inspection. Refer to INSPECTION [03/2012 - ] .
3. Inspect the function of the mass air flow meter sub-assembly.
   1. Connect the Techstream to the DLC3.
   2. Turn the engine switch on (IG).
   3. Turn the Techstream on.
   4. Enter the following menus: Powertrain / Engine / Data List / MAF.
   5. Start the engine.
   6. Check that the MAF value changes when the engine is raced.

      OK

      The reading changes.

NG → See step   7 

OK → See step   8 

1. Disconnect the mass air flow meter sub-assembly connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   D3-4 (E2G) - Body ground	Always	Below 1 Ω

3. Reconnect the mass air flow meter sub-assembly connector.

NG → See step   6 

OK → See step   7 

1. Disconnect the mass air flow meter sub-assembly 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
   D3-4 (E2G) - D1-75 (E2G)	Always	Below 1 Ω

4. Reconnect the mass air flow meter sub-assembly connector.
5. Reconnect the ECM connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM) 

OK → See step   8