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. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
4. 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 

Fig 1: Identifying 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
   B2-3 (+B) - Body ground	Ignition switch ON	11 to 14 V

4. Reconnect the mass air flow meter connector.

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

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) - B29-69 (VG)	Always	Below 1 Ω
   B2-4 (E2G) - B29-92 (E2G)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   B2-5 (VG) or B29-69 (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 (MASS AIR FLOW METER - ECM) 

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. Start the engine.
   5. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / MAF.
   6. Check that the reading of 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 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   6 

OK → See step   7 

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) - B29-92 (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 (MASS AIR FLOW METER - ECM) 

OK → See step   8