Inspection Procedure

HINT:

Read freeze frame data using the hand-held tester. 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 DATA LIST (INTAKE AIR TEMPERATURE) 
   1. Connect the hand-held tester to the DLC3.
   2. Turn the ignition switch ON and turn the hand-held tester ON.
   3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
   4. Read the values.

      Standard: Same value as the actual IAT. 

   Result: 

   INTAKE AIR TEMPERATURE SPECIFICATIONS
   
   

   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 hand-held tester indicates -40°C (-40°F).
   • If there is a short circuit, the hand-held tester indicates 140°C (284°F) or more.
   1. B: Go to step   4 . 
   2. C: See  CHECK FOR INTERMITTENT PROBLEMS   ) 
   3. A: Go to next step. 
2. READ DATA LIST (CHECK FOR OPEN IN WIRE HARNESS) 
   1. Disconnect the M1 MAF meter connector.
   2. Connect terminals THA and E2 of the MAF meter wire harness side connector.
   3. Connect the hand-held tester to the DLC3.
   4. Turn the ignition switch ON and turn the hand-held tester ON.
   5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
   6. Read the values.

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

      Fig 1: Connecting Terminals THA & E2 Of MASS Air Flow Meter Wire Harness Side Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. OK: REPLACE MASS AIR FLOW METER 
   2. NG: Go to next step. 
3. READ DATA LIST (CHECK FOR OPEN IN ECM) 
   1. Disconnect the M1 MAF meter connector.
   2. Connect terminals THA and ETHA of the E4 ECM connector.

      HINT:

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

   3. Connect the hand-held tester to the DLC3.
   4. Turn the ignition switch ON and turn the hand-held tester ON.
   5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
   6. Read the values.

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

      Fig 2: Connecting Terminals THA & ETHA Of E4 ECM Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG: REPLACE ECM (See  REPLACEMENT  ) 
   2. OK: REPLACE OR REPLACE HARNESS AND CONNECTOR 
4. READ DATA LIST (CHECK FOR SHORT IN WIRE HARNESS) 
   1. Disconnect the M1 MAF meter connector.
   2. Connect the hand-held tester to the DLC3.
   3. Turn the ignition switch ON and turn the hand-held tester ON.
   4. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
   5. Read the values.

      Standard: -40°C (-40°F) 

      Fig 3: Connecting Terminals THA & E2 Of E8 ECM Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. OK: REPLACE MASS AIR FLOW METER 
   2. NG: Go to next step. 
5. READ DATA LIST (CHECK FOR SHORT IN HARNESS OR ECM) 
   1. Disconnect the M1 MAF meter connector.
   2. Disconnect the E4 ECM connector.
   3. Connect the hand-held tester to the DLC3.
   4. Turn the ignition switch ON and turn the hand-held tester ON.
   5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
   6. Read the values.

      Standard: -40°C (-40°F) 

      Fig 4: Connecting Terminals THA & E2 Of E8 ECM Connector

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