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On-Vehicle Inspection

  1. REMOVE ENGINE COVER 

    Remove the 4 nuts and engine cover.

  2. INSPECT SYSTEM OPERATION 
    1. Check that the throttle linkage moves smoothly.
      Fig 1: Checking Throttle Linkage Moves Smoothly
      G02949260Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Inspect the throttle control motor for operating sound.
      1. Turn the ignition switch ON.
      2. When turning the accelerator pedal position sensor lever, check the running sound of the motor. Also, check that there is no friction sound.

      If operation is not as specified, check the throttle control motor, wiring and ECM.

      Fig 2: Inspecting Throttle Control Motor For Operating Sound
      G02949261Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Inspect the throttle position sensor and accelerator pedal position sensor function.
      1. Connect the hand-held tester to the DLC3.
      2. Fig 3: Connecting Hand-Held Tester To DLC3
        G02949262Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. When turning the accelerator pedal position sensor lever to the full-open position.
      4. Select the following menu, DIAGNOSIS/ENHANCED OBD II/DATA LIST/THROTTLE POS.

        Throttle valve opening percentage: 60% or more 

      If operation is not as specified, check that the throttle position sensor, accelerator pedal position sensor, wiring and ECM.

    4. Start the engine, and check that the Malfunction Indicator Lamp (MIL) does not light up.
    5. Inspect the air assist system.
      1. Allow the engine to warm up to normal operating temperature.
      2. Turn the A/C switch ON and OFF, and check the idle speed.

        Idle speed (Transmission in neutral): 

        700 +/- 50 RPM (A/C OFF) 

        750 +/- 50 RPM (A/C ON) 

        NOTE: Perform inspection under condition without electrical load.
      3. With engine idling, pinch the air assist hose and check that engine speed drops, and then returns back up to idle speed.

      If operation is not as specified, check the throttle body, wiring and ECM.

    6. After checking the above (b) to (e), perform the diving test and check that there is no sense of incongruity.
      Fig 4: Pinching Air Assist Hose And Checking That Engine Speed Drops
      G02949263Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. INSPECT THROTTLE CONTROL MOTOR 
    1. Disconnect the throttle control motor connector.
    2. Using an ohmmeter, measure the resistance between terminal 3 (CL-) and 4 (CL+).

      Resistance: 4.2-5.2 Ω at 20°C (68°F) 

    3. Using an ohmmeter, measure the resistance between terminal 1 (M+) and 2 (M-).

      Resistance: 0.3-100 Ω at 20°C (68°F) 

      Fig 5: Measuring Resistance Between Throttle Control Motor Connector Terminals
      G02949264Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the resistance is not as specified, replace the throttle control motor (See REPLACEMENT ).

    4. Reconnect the throttle control motor connector.
  4. INSPECT THROTTLE POSITION SENSOR 
    1. Disconnect the throttle position sensor connector.
    2. Using an ohmmeter, measure the resistance between terminals VC and E2.

      Resistance: 1.2-3.2 kΩ at 20°C (68°F) 

      If the resistance is not as specified, replace the throttle position sensor (See REPLACEMENT ).

      Fig 6: Measuring Resistance Between Throttle Position Sensor Connector Terminals
      G02949265Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reconnect the throttle position sensor connector.
  5. INSPECT ACCELERATOR PEDAL POSITION SENSOR 
    1. Disconnect the accelerator pedal position sensor connector.
    2. Using an ohmmeter, measure the resistance between terminals VC and E2.

      Resistance: 1.2-3.2 kΩ at 20°C (68°F) 

      If the resistance is not as specified, replace the accelerator pedal position sensor (See REPLACEMENT ).

      Fig 7: Measuring Resistance Between Accelerator Pedal Position Sensor Connector Terminals
      G02949266Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reconnect the accelerator pedal position sensor connector.
  6. REINSTALL ENGINE COVER 

    Install the engine cover with the 4 nuts.