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
   
   

   MAF (gm/s)	Proceed to
   0.0	A
   160.0 or more	B
   Between 1.0 and 160.0*	C

   HINT: 

   *: The value must change when the throttle valve is opened or closed with the engine running.

B → See step   6 

C → See step   8 

A: Go to next step 

Fig 1: Identifying C27 Mass Air Flow Meter Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the mass air flow 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
   C27-1 (+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 Assembly)

NG → See step   5 

OK: Go to next step 

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C27-3 (VG) - C29-14 (VG)	Always	Below 1 Ω
   C27-2 (E2G) - C29-13 (E2G)	Always	Below 1 Ω
   C27-3 (VG) or C29-14 (VG) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Inspect the mass air flow meter assembly. Refer to ON-VEHICLE INSPECTION - Step 1 .

NG → See step   9 

OK → See step   13 

1. Disconnect the mass air flow meter connector.
2. Remove the No. 1 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
   C27-1 (+B) - 1B-4	Always	Below 1 Ω
   C27-1 (+B) or 1B-4 - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   11 

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C27-3 (VG) - C29-14 (VG)	Always	Below 1 Ω
   C27-2 (E2G) - C29-13 (E2G)	Always	Below 1 Ω
   C27-3 (VG) or C29-14 (VG) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Disconnect the 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
   C27-2 (E2G) - Body ground	Always	Below 1 Ω

NG → See step   10 

OK → See step   12