Inspection Procedure

HINT:

• If other DTCs relating to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.
• Read freeze frame data using the Techstream The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction

1. READ VALUE USING TECHSTREAM (INTAKE AIR TEMPERATURE) 
   1. Connect the Techstream to the DLC3
   2. Turn the engine switch on (IG).
   3. Turn the Techstream ON
   4. Enter the following menus Powertrain / Engine / Data List/ Intake Air
   5. Read the value displayed on the Techstream

      Standard: Same as actual intake air temperature. 

      Result 

      RESULT CHART
      
      

      Temperature Displayed	Proceed to
      -40°C (-40°F)	A
      140°C (284°F)	B
      Same as actual intake air temperature	C

      HINT

      • If there is an open circuit, the Techstream indicates 40°C (-40°F)
      • If there is a short circuit, the Techstream indicates 140°C (284°F).

   B: Go to step  4

   C: CHECK FOR INTERMITTENT PROBLEMS  (See CHECK FOR INTERMITTENT PROBLEMS )

   A: Go to next step 

2. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS) 
   1. Disconnect the mass air flow meter connector
   2. Connect terminals THA and E2 of the mass air flow meter wire harness connector.
   3. Connect the Techstream to the DLC3
   4. Turn the engine switch on (IG)
   5. Turn the Techstream ON.
   6. Enter the following menus: Powertrain / Engine / Data List/ Intake Air.
   7. Read the value displayed on the Techstream

      Standard: 140°C (284°F) 

   8. Reconnect the mass air flow meter connector.
   Fig 1: Identifying Mass Air Flow Meter Connector Terminal E29
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG: Go to step 3 

   OK: REPLACE MASS AIR FLOW METER  (See REMOVAL )

3. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN ECM) 
   1. Disconnect the mass air flow meter connector
   2. Connect terminals THA and E2 of the ECM connector

      HINT

      Before checking, do visual and contact pressure checks on the ECM connector

   3. Connect the Techstream to the DLC3
   4. Turn the engine switch on (IG)
   5. Turn the Techstream ON.
   6. Enter the following menus Powertrain / Engine / Data List / Intake Air
   7. Read the value displayed on the Techstream

      Standard: 140°C (284°F) 

   8. Reconnect the mass air flow meter connector
   Fig 2: Identifying Mass Air Flow Meter And ECM Circuit With ECM Connectors Terminals
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG: REPLACE ECM  (See REMOVAL )

   OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

4. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS) 
   1. Disconnect the mass air flow meter connector
   2. Connect the Techstream to the DLC3
   3. Turn the engine switch on (IG).
   4. Turn the Techstream ON.
   5. Enter the following menus. Powertrain / Engine / Data List/ Intake Air
   6. Read the value displayed on the Techstream

      Standard: -40°C (-40°F) 

   7. Reconnect the mass airflow meter connector.
   Fig 3: Identifying Mass Airflow Meter And ECM Circuit
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG: Go to step 5 

   OK: REPLACE MASS AIR FLOW METER  (See REMOVAL )

5. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN ECM) 
   1. Disconnect the mass air flow meter connector
   2. Disconnect the ECM connector.
   3. Connect the Techstream to the DLC3
   4. Turn the engine switch on (IG).
   5. Turn the Techstream ON
   6. Enter the following menus Powertrain / Engine / Data List/ Intake Air
   7. Read the value displayed on the Techstream.

      Standard: -40°C (-40°F) 

   8. Reconnect the mass air flow meter connector
   Fig 4: Identifying Mass Air Flow Meter And ECM Circuit With ECM Connectors Terminals
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG: REPLACE ECM  (See REMOVAL )

   OK: REPAIR OR REPLACE HARNESS OR CONNECTOR