Inspection Procedure

HINT:

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 (MASS AIR FLOW RATE) 
   1. Connect a Techstream to the DLC3.
   2. Start the engine.
   3. Turn the tester ON.
   4. Select the following menu items: Powertrain / Engine and ECT / Data List / All Data / MAR
   5. Read the values displayed on the tester.

      Result 

      RESULT REFERENCE
      
      

      Mass Air Flow Rate (g/sec)	Proceed To
      0.0	A
      271.0 or more	B
      Between 1.0 and 270.0 ((1))	C
      (1) The value must be changed when the throttle valve is open or closed.

      B: Go to step  6

      C: CHECK FOR INTERMITTENT PROBLEMS 

      A: Go to next step 

2. INSPECT MASS AIR FLOW METER (POWER SOURCE VOLTAGE) 
   Fig 1: Identifying Mass Air Flow Meter Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Disconnect the B13 Mass Air Flow (MAF) meter connector.
   2. Turn the ignition switch ON.
   3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
      
      

      Tester Connections	Specified Conditions
      +B (B13-1) Body ground	11 to14V

   4. Reconnect the MAF meter connector.

   NG: Go to step  5

   OK: Go to Next Step 

3. INSPECT ECM (VG VOLTAGE) 
   Fig 2: Identifying ECM Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Start the engine.
   2. Measure the voltage according to the value(s) in the table below.

      HINT:

      The transmission gear selector lever should be in the P or N position and the A/C switch should be turned OFF.

      Standard Voltage 

      TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
      
      

      Tester Connections	Conditions	Specified Conditions
      VG(B1-30)-E2G(B1-29)	Engine idling	0.5 to 3.0 V

   OK: REPLACE ECM  (See REMOVAL  )

   NG: Go to Next Step 

4. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER ECM) 
   1. Disconnect the B13 MAF meter connector.
   Fig 3: Identifying B13 MAF Meter Connector And B1 ECM Connector
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Disconnect the B1 ECM connector.
   3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open) 

      TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
      
      

      Tester Connections	Specified Conditions
      VG (B13-3)-VG(B1-30)	Below 1 Ω
      E2G (B13-2)-E2G(B1-29)

      Standard Resistance (Check for short) 

      TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
      
      

      Tester Connections	Specified Conditions
      VG (B13-3) or VG (B1-30) Body ground	10 kΩ or higher

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

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   OK: REPLACE MASS AIR FLOW METER  (See REMOVAL  )

5. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER EFI RELAY) 
   1. Inspect the EFI NO. 2 fuse.
      1. Remove the EFI NO. 2 fuse from the engine room relay block.
      2. Check the EFI NO. 2 fuse resistance.

         Standard Resistance: Below 1 Ω 

      3. Reinstall the EFI NO. 2 fuse.
   2. Disconnect the B13 MAF meter connector.
   Fig 4: Identifying B13 MAF Meter Connector And EFI No. 2 Fuse
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   3. Remove the EFI relay from the engine room relay block.
   4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open) 

      TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
      
      

      Tester Connections	Specified Conditions
      +B(B13-1)-EFI relay(3)	Below 1 Ω

      Standard Resistance (Check for short) 

      TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
      
      

      Tester Connections	Specified Conditions
      +B (B13-1) or EFI relay (3) Body ground	10 kΩ or higher

   5. Reconnect the MAF meter connector.
   6. Reinstall the EFI relay.

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   OK: CHECK ECM POWER SOURCE CIRCUIT 

6. INSPECT ECM (SENSOR GROUND) 
   1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
      
      

      Tester Connections	Specified Conditions
      E2G (B1-29) Body ground	Below 1 Ω

      Fig 5: Identifying ECM Connectors

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG: REPLACE ECM  (See REMOVAL  )

   OK: Go to Next Step 

7. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER ECM) 
   1. Disconnect the B13 MAF meter connector.
   Fig 6: Identifying B13 MAF Meter Connector And ECM Connectors
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Disconnect the B1 ECM connector.
   3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open) 

      TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
      
      

      Tester Connections	Specified Conditions
      VG(B13-3)-VG(B1-30)	Below 1 Ω
      E2G(B13-2)-E2G(B1-29)

      Standard Resistance (Check for short) 

      TESTER CONNECTIONS SPECIFIED CONDITIONS CHART
      
      

      Tester Connections	Specified Conditions
      VG (B13-3) or VG (B1-30) Body ground	10 kΩ or higher

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

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   OK: REPLACE MASS AIR FLOW METER  (See REMOVAL  )