Inspection Procedure

HINT:

Read freeze frame data using the Techstream. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, 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 OF TECHSTREAM (INTAKE AIR TEMPERATURE) 
   1. Connect the Techstream to the DLC3.
   2. Turn the ignition switch ON and turn the tester ON.
   3. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.
   4. Read the values.

      OK: 

      Same value as the actual IAT 

      Result 

      RESULT CHART
      
      

      Intake Air Temperature	Proceed to
      -40°C (-40°F)	A
      140°C (284°F) or more	B
      OK (same as present 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) or more.

      B:  Go to step  4

      C: CHECK FOR INTERMITTENT PROBLEMS 

      A: Go to Next Step 

2. READ VALUE OF TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS) 
   1. Disconnect the M1 MAF meter connector.
   2. Connect terminal THA and E2 of the MAF meter's wire harness side connector.
   3. Connect the Techstream to the DLC3.
   4. Turn the ignition switch ON and turn the tester ON.
   5. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.
   6. Read the value.

      OK: 

      Temperature value is 140°C (284°F) or more 

      OK: REPLACE MASS AIR FLOW METER 

      Fig 1: Checking For Open In Wire Harness

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: Go to Next Step 

3. READ VALUE OF TECHSTREAM (CHECK FOR OPEN IN ECM) 
   1. Disconnect the M1 MAF meter connector.
   2. Connect terminal THA of the E4 ECM connector and terminal E2 of the E2 ECM connector.

      HINT:

      Before checking, perform a visual and contact pressure check for the ECM connector.

   3. Connect the Techstream to the DLC3.
   4. Turn the ignition switch ON and turn the tester ON.
   5. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.
   6. Read the value.

      OK: 

      Temperature value is 140°C (284°F) or more 

      NG: REPLACE ECM 

      Fig 2: Checking For Open In ECM

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPAIR OR REPLACE HARNESS AND CONNECTOR 

4. READ VALUE OF TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS) 
   1. Disconnect the M1 MAF meter connector.
   2. Connect the Techstream to the DLC3.
   3. Turn the ignition switch ON and turn the tester ON.
   4. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.
   5. Read the value.

      OK: 

      Temperature value is -40°C (-40°F) 

      OK: REPLACE MASS AIR FLOW METER 

      Fig 3: Checking For Short In Wire Harness

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: Go to Next Step 

5. READ VALUE OF TECHSTREAM (CHECK FOR SHORT IN HARNESS OR ECM) 
   1. Disconnect the M1 MAF meter connector.
   2. Disconnect the E2 and E4 ECM connectors.
   3. Connect the Techstream to the DLC3.
   4. Turn the ignition switch ON and turn the tester ON.
   5. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.
   6. Read the value.

      OK: 

      Temperature value is -40°C (-40°F) 

      NG: REPLACE ECM 

      Fig 4: Checking For Short In Harness Or ECM

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPAIR OR REPLACE HARNESS AND CONNECTOR