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 hand-held tester or OBD II scan tool. 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 HAND-HELD TESTER OR OBD II SCAN TOOL (INTAKE AIR TEMPERATURE) 
   1. Connect a hand-held tester or OBD II scan tool to the DLC3.
   2. Turn the ignition switch to ON.
   3. Turn the tester or scan tool ON.
   4. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
   5. Read the value displayed on the tester.
   6. If using an OBD II scan tool, refer to the instruction manual.

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

      Result: 

      TEMPERATURE SPECIFICATIONS
      
      

      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 hand-held tester or OBD II scan tool indicates -40°C (-40°F).
      • If there is a short circuit, the hand-held tester or OBD II scan tool indicates 140°C (284°F) or higher.
   1. B : Go to step   4 
   2. C : (See  CHECK FOR INTERMITTENT PROBLEMS   ) 
   3. A : GO TO NEXT STEP 
2. READ VALUE USING HAND-HELD TESTER OR OBD II SCAN TOOL (CHECK FOR OPEN IN WIRE HARNESS) 
   1. Disconnect the M1 Mass Air Flow (MAF) meter connector.
   2. Connect terminals THA and E2 of the MAF meter wire harness side connector.
   3. Connect the hand-held tester or OBD II scan tool to the DLC3.
   4. Turn the ignition switch to ON.
   5. Turn the tester or scan tool ON.
   6. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
      Fig 1: Disconnecting M1 Mass Air Flow (MAF) Meter Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   7. Read the value displayed on the tester.
   8. If using an OBD II scan tool, refer to the instruction manual.

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

   9. Reconnect the MAF meter connector.
      Fig 2: Connecting Terminals THA & E2 Of MAF Meter Wire Harness Side Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. OK : CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE MASS AIR FLOW METER 
   2. NG : GO TO NEXT STEP 
3. READ VALUE USING HAND-HELD TESTER OR OBD II SCAN TOOL (CHECK FOR OPEN IN ECM) 
   1. Disconnect the M1 MAF meter connector.
   2. Connect terminals THA and E2 of the E3 ECM connector.

      HINT:

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

   3. Connect the hand-held tester or OBD II scan tool to the DLC3.
   4. Turn the ignition switch to ON.
   5. Turn the tester or scan tool ON.
   6. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
      Fig 3: Disconnecting M1 MAF Meter Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   7. Read the value displayed on the tester.
   8. If using an OBD II scan tool, refer to the instruction manual.

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

   9. Reconnect the MAF meter connector.
      Fig 4: Connecting Terminals THA & E2 Of E3 ECM Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. OK : REPAIR OR REPLACE HARNESS OR / CONNECTOR 
   2. NG : CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM (See  REPLACEMENT  ) 
4. READ VALUE USING HAND-HELD TESTER OR OBD II SCAN TOOL (CHECK FOR SHORT IN WIRE HARNESS) 
   1. Disconnect the M1 MAF meter connector.
   2. Connect the hand-held tester or OBD II scan tool to the DLC3.
   3. Turn the ignition switch to ON.
   4. Turn the tester or scan tool ON.
   5. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
   6. Read the value displayed on the tester.
   7. If using an OBD II scan tool, refer to the instruction manual.

      Standard: -40°C (-40°F) 

   8. Reconnect the MAF meter connector.
      Fig 5: Disconnecting M1 MAF Meter Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. OK : REPLACE MASS AIR FLOW METER 
   2. NG : GO TO NEXT STEP 
5. READ VALUE USING HAND-HELD TESTER OR OBD II SCAN TOOL (CHECK FOR SHORT IN ECM) 
   1. Disconnect the E3 ECM connector.
   2. Connect the hand-held tester or OBD II scan tool to the DLC3.
   3. Turn the ignition switch to ON.
   4. Turn the tester or scan tool ON.
   5. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
   6. Read the value displayed on the tester.
      Fig 6: Disconnecting M1 MAF Meter Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   7. If using an OBD II scan tool, refer to the instruction manual.

      Standard: -40°C (-40°F) 

   8. Reconnect the ECM connector.
      Fig 7: Disconnecting E3 ECM Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. OK : REPAIR OR REPLACE HARNESS OR CONNECTOR 
   2. NG : REPLACE ECM (See  REPLACEMENT  )