DTC P0102: Mass or Volume Air Flow Circuit Low Input (FROM 12/2010); DTC P0103: Mass or Volume Air Flow Circuit High Input (FROM 12/2010): Procedure

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Select the following menu items: 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   6 

A: Go to next step 

1. Disconnect the mass air flow (MAF) meter connector.
   Fig 1: Identifying B10 Mass Air Flow (MAF) Meter Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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
   B10-3 (+B) - Body ground	Ignition switch ON	11 to 14 V

4. Reconnect the MAF meter connector.

NG → See step   5 

OK: Go to next step 

1. Disconnect the MAF meter connector.
2. Disconnect the ECM connector.
3. Measure the resistance between the terminals.

   Standard resistance (Check for open)

   Tester Connection	Condition	Specified Condition
   B50-72 (VG) - B10-5 (VG)	Always	Below 1 Ω
   B50-73 (E2G) - B10-4 (E2G)	Always	Below 1 Ω

   Standard resistance (Check for short)

   Tester Connection	Condition	Specified Condition
   B50-72 (VG) or B10-5 (VG) - Body ground	Always	10 kΩ or higher

4. Reconnect the MAF 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. 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 / Data List / All Data / MAF.
   5. Start the engine.
   6. Check that the reading of the mass air flow meter changes when the engine is raced.

   OK

   The reading changes.

NG → REPLACE MASS AIR FLOW METER 

OK → See step   8 

1. Remove the EFI No. 2 fuse from the engine room R/B.
   Fig 2: Identifying EFI No. 2 Fuse

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the EFI No. 2 fuse resistance.

   Standard resistance

   Below 1 Ω

3. Reinstall the EFI No. 2 fuse.

NG → REPLACE FUSE (EFI NO. 2 FUSE) 

OK → REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI RELAY - MASS AIR FLOW METER) 

1. Disconnect the MAF meter connector.
2. Measure the resistance between the terminals.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   B10-4 (E2G) - Body ground	Always	Below 1 Ω

3. Reconnect the MAF meter connector.

OK → REPLACE MASS AIR FLOW METER 

NG: Go to next step 

1. Disconnect the MAF meter connector.
2. Disconnect the ECM connector.
3. Measure the resistance between the terminals.

   Standard resistance (Check for open)

   Tester Connection	Condition	Specified Condition
   B50-73 (E2G) - B10-4 (E2G)	Always	Below 1 Ω

4. Reconnect the MAF meter connector.
5. Reconnect the ECM connector.

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

OK → See step   8