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 ignition switch to ON.
3. Turn the Techstream on.
4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
5. Read DTCs.
   RESULT
   
   

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

B → See step   5 

A: Go to next step 

Fig 1: Measuring Voltage Of Mass Air Flow Meter Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the mass air flow 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
   C23-3 (+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)

NG → See step   7 

OK: Go to next step 

1. Disconnect the C23 mass air flow meter connector.
2. Disconnect the C19 ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C23-5 (VG) - C19-69 (VG)	Always	Below 1 Ω
   C23-4 (E2G) - C19-92 (E2G)	Always	Below 1 Ω
   C23-5 (VG) or C19-69 (VG) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Perform On-vehicle inspection. Refer to ON-VEHICLE INSPECTION .
2. Perform Inspection. Refer to INSPECTION .
3. Inspect the function of the mass air flow meter.
   1. Connect the Techstream to the DLC3.
   2. Turn the ignition switch to ON.
   3. Turn the Techstream on.
   4. Enter the following menus: Powertrain / Engine and ECT / Data List / MAF.
   5. Check that the mass air flow meter value changes when the engine is raced.

      OK

      The reading changes.

NG → See step   8 

OK → See step   9 

1. Disconnect the C23 mass air flow meter connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C23-4 (E2G) - Body ground	Always	Below 1 Ω

NG → See step   6 

OK → See step   11 

1. Disconnect the C23 mass air flow meter connector.
2. Disconnect the C19 ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C23-4 (E2G) - C19-92 (E2G)	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   12 

1. Disconnect the C23 mass air flow meter connector.
2. Remove the integration relay from the engine room relay block.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C23-3 (+B) - 1A-4	Always	Below 1 Ω
   C23-3 (+B) or 1A-4 - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   10