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   6 

A: Go to next step 

Fig 1: Inspect Mass Air Flow Meter (Power Source Voltage)

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
   B2-3 (+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)

4. Reconnect the mass air flow meter connector.

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 (Check for Open)

   Tester Connection	Condition	Specified Condition
   B2-5 (VG) - B33-118 (VG)	Always	Below 1 Ω
   B2-4 (E2G) - B33-116 (E2G)

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   B2-5 (VG) or B33-118 (VG) - Body ground	Always	10 kΩ or higher

4. Reconnect the mass air flow meter connector.
5. Reconnect the ECM connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Inspect the mass air flow meter, referring to the On-vehicle Inspection for Mass Air Flow Meter. Refer to ON-VEHICLE INSPECTION .
2. Inspect the mass air flow meter, referring to the Inspection for Mass Air Flow Meter. 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. Start the engine.
4. Check that the MAF value changes when the engine is raced.

   OK

   The reading changes.

NG → See step   10 

OK → See step   11 

1. Disconnect the mass air flow meter connector.
2. Remove the integration relay (EFI MAIN 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
   B2-3 (+B) - 1B-4	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   B2-3 (+B) or 1B-4 - Body ground	Always	10 kΩ or higher

4. Reconnect the mass air flow meter connector.
5. Reinstall the integration relay.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   9 

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
   B2-4 (E2G) - Body ground	Always	Below 1 Ω

3. Reconnect the mass air flow meter connector.

NG → See step   7 

OK → See step   10 

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 (Check for Open)

   Tester Connection	Condition	Specified Condition
   B2-4 (E2G) - B33-116 (E2G)	Always	Below 1 Ω

4. Reconnect the mass air flow meter connector.
5. Reconnect the ECM connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   8