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 power switch on (IG).
3. Turn the Techstream on.
4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
5. 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: Inspect Mass Air Flow Meter Sub-Assembly (Power Source Voltage)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the mass air flow meter sub-assembly connector.
2. Turn the power switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   D5-3 (+B) - Body ground	Power switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Mass Air Flow Meter Sub-assembly)

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

OK: Go to next step 

1. Disconnect the mass air flow meter sub-assembly 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
   D5-5 (VG) - D28-94 (VG)	Always	Below 1 Ω
   D5-4 (E2G) - D28-117 (E2G)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   D5-5 (VG) or D28-94 (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 sub-assembly, referring to the On-vehicle Inspection for Mass Air Flow Meter. Refer to ON-VEHICLE INSPECTION .
2. Inspect the mass air flow meter sub-assembly, referring to the Inspection for Mass Air Flow Meter. Refer to INSPECTION .
3. Inspect the function of the mass air flow meter sub-assembly.
   1. Connect the Techstream to the DLC3.
   2. Turn the power switch on (IG).
   3. Turn the Techstream on.
   4. Put the engine in inspection mode (maintenance mode). Refer to INSPECTION MODE PROCEDURE .
   5. Start the engine.
   6. Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / MAF.
   7. Check that the MAF value changes when the engine is raced.

      OK

      The reading changes.

NG → See step   8 

OK → See step   7 

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

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   D5-4 (E2G) - Body ground	Always	Below 1 Ω

NG → See step   6 

OK → See step   8 

1. Disconnect the mass air flow meter sub-assembly 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
   D5-4 (E2G) - D28-117 (E2G)	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   7