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 a Techstream. Freeze frame data record the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

1. READ VALUE USING TECHSTREAM (INTAKE AIR TEMPERATURE) 
   1. Connect a Techstream to the DLC3.
   2. Turn the ignition switch ON.
   3. Turn the tester ON.
   4. Select the following menu items: Powertrain / Engine and ECT / Data List / All Data / Intake Air.
   5. Read the value displayed on the tester.

      Standard: Same as actual Intake Air Temperature (IAT). 

      Result 

      RESULT REFERENCE
      
      

      Temperature Displayed	Proceed To
      -40°C (-40°F)	A
      140°C (284°F) or higher	B
      Same as actual IAT	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) or higher.

   B: Go to step   4

   C: CHECK FOR INTERMITTENT PROBLEMS 

   A: Go to next step 

2. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS) 
   1. Disconnect the B13 Mass Air Flow (MAF) meter connector.
   Fig 1: Identifying B13 Mass Air Flow (MAF) Meter Connector
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Connect terminals THA and E2 of the MAF meter wire harness side connector.
   3. Connect a Techstream to the DLC3.
   4. Turn the ignition switch ON.
   5. Turn the tester ON.
   6. Select the following menu items: Powertrain / Engine and ECT / Data List / All Data / Intake Air.
   7. Read the value displayed on the tester.

      Standard: 140°C(284°F) or higher 

   8. Reconnect the MAF meter connector.

   OK: CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE MASS AIR FLOW METER  (See REMOVAL  )

   NG: Go to Next Step 

3. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN ECM) 
   1. Disconnect the B13 MAF meter connector.
   Fig 2: MAF Meter Connector - Communication Diagram
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Connect terminals THA and E2 of the B1 ECM connector.

      HINT:

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

   3. Connect a Techstream to the DLC3.
   4. Turn the ignition switch ON.
   5. Turn the tester ON.
   6. Select the following menu items: Powertrain / Engine and ECT / Data List / All Data / Intake Air.
   7. Read the value displayed on the tester.

      Standard: 140°C (284°F) or higher. 

   8. Reconnect the MAF meter connector.

   OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   NG: CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM  (See REMOVAL  )

4. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS) 
   1. Disconnect the B13 MAF meter connector.
   Fig 3: MAF Meter Connector - Communication Diagram
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Connect a Techstream to the DLC3.
   3. Turn the ignition switch ON.
   4. Turn the tester ON.
   5. Select the following menu items: Powertrain / Engine and ECT / Data List / All Data / Intake Air.
   6. Read the value displayed on the tester.

      Standard: -40°C (-40°F) 

   7. Reconnect the MAF meter connector.

   OK: REPLACE MASS AIR FLOW METER  (See REMOVAL  )

   NG: Go to Next Step 

5. READ VALUE USING TECHSTREAM (CHECK FOR SHORT ECM) 
   1. Disconnect the B1 ECM connector.
      Fig 4: Identifying MAF Meter & ECM Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Connect a Techstream to the DLC3.
   3. Turn the ignition switch ON.
   4. Turn the tester ON.
   5. Select the following menu items: Powertrain / Engine and ECT / Data List / All Data / Intake Air.
   6. Read the value displayed on the tester.

      Standard: -40°C (-40°F) 

   7. Reconnect the ECM connector.

   OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   NG: REPLACE ECM  (See REMOVAL  )