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Home >> Lexus >> 2017 >> IS 300 F Sport >> Repair and Diagnosis >> External Pages >> Different car >> Section 175 (Automatic Transmission System (A760H) - Diagnostic Codes (3 Of 3) & Circuit Tests) >> AUTOMATIC TRANSMISSION SYSTEM (for 2GR-FKS) >> DTC P0781-00: 1-2 Shift [10/2017 - 09/2019] >> Procedure

DTC P0781-00: 1-2 Shift [10/2017 - 09/2019]: Procedure

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  1. CHECK IF OTHER DTCS OUTPUT 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Transmission / Trouble Codes.

      Powertrain > Transmission > Trouble Codes 

    5. Read the DTCs using the Techstream.

      Result

      Result Proceed to
      Only DTC P0781-00 is output A
      P0781-00 and other DTCs are output B

      HINT: 

      If any DTCs other than P0781-00 are output, perform troubleshooting for those DTCs first.

    Result: 

    B 

    GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2017 - 09/2018]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2018 - 09/2019] 

    Result: 

    A 

    See step  2

  2. PERFORM ACTIVE TEST USING TECHSTREAM 
    WARNING:

    This test should always be performed with at least 2 people.

    NOTE:
    • Perform the test while the ATF temperature is between 50 and 80°C (122 and 176°F).
    • Perform the test with the air conditioning off.

    HINT: 

    Using the Techstream to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests.

    1. Warm up the engine.
    2. Turn the engine switch off.
    3. Connect the Techstream to the DLC3.
    4. Turn the engine switch on (IG).
    5. Turn the Techstream on.
    6. Enter the following menus: Powertrain / Transmission / Active Test.
    7. According to the display on the Techstream, perform the "Active Test".

      HINT: 

      While driving, the shift position can be forcibly changed with the Techstream. Comparing the shift position commanded by the Active Test with the actual shift position enables you to confirm the problem.

      Refer to FAIL-SAFE CHART [10/2017 - ]

      Powertrain > Transmission > Active Test 

      Tester Display Measurement Item Control Range Diagnostic Note
      Control the Shift Position Operates the shift solenoid valves to allow gears to be selected manually 1st/2nd/3rd/4th/5th/6th
      Start/Stop      		 Possible to check operation of the shift solenoid valves.
      [Vehicle Condition] 
      1. Vehicle speed: 50 km/h (31 mph) or less

      Powertrain > Transmission > Active Test 

      Tester Display
      Control the Shift Position

      HINT: 

      • This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.
      • The 4th to 5th and 5th to 6th up-shifts must be performed with the accelerator pedal released.
      • The 6th to 5th and 5th to 4th down-shifts must be performed with the accelerator pedal released.
      • Do not operate the accelerator pedal for at least 2 seconds after shifting and do not shift successively.
      • The shift position commanded by the ECM is shown in the Data List (Shift Status) display on the Techstream.
      • Gear positions in the event of a shift solenoid valve mechanical problem:
        Techstream command gear shift 1st 2nd 3rd 4th 5th 6th
        Actual gear position under malfunction 1st 1st 3rd 3rd N* N*

        *: Neutral

      OK

      Gear position changes in accordance with the Techstream command.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY. Refer to  COMPONENTS [04/2013 - ] 

    Result: 

    OK 

    See step  3

  3. PERFORM ACTIVE TEST USING TECHSTREAM 
    NOTE:
    • Perform the test at the normal operating ATF (Automatic Transmission Fluid) temperature: 50 to 80°C (122 to 176°F)
    • Be careful to prevent the SST hose from interfering with the exhaust pipe.
    • This check must be conducted after checking and confirming that the engine is normal.
    • Perform the test with the air conditioning off.

    HINT: 

    Using the Techstream to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests.

    1. Turn the engine switch off.
    2. Lift the vehicle up.
    3. Remove the test plug from the transmission case and connect SST.
      GTY680648Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • SST: 09993-19016 
        1. 09993-00011
        2. 09993-00041
    4. Lower the vehicle.
    5. Fully apply the parking brake and chock all 4 wheels.
    6. Connect the Techstream to the DLC3.
    7. Start the engine.
    8. Warm up the ATF (Automatic Transmission Fluid).
    9. Measure the line pressure when the engine is idling.
    10. Turn the Techstream on.
    11. Enter the following menus: Powertrain / Transmission / Active Test.
    12. According to the display on the Techstream, perform the "Active Test".
    13. Measure the line pressure with SST.

      Powertrain > Transmission > Active Test 

      Tester Display Measurement Item Control Range Diagnostic Note
      Activate the Solenoid (SLT) Operates the shift solenoid valve SLT and raise line pressure ON/OFF
      HINT: 
      ON: No action (normal operation)
      OFF: Line pressure up (When the Active Test of "Activate the Solenoid (SLT)" is performed, the ECM commands the SLT solenoid to turn off).      		 [Vehicle Condition] 
      • Vehicle stopped
      • Engine idling

      Powertrain > Transmission > Active Test 

      Tester Display
      Activate the Solenoid (SLT)

      "Activate the Solenoid (SLT)" in the Active Test is performed to check the line pressure changes by connecting SST to the automatic transmission, which is used in the HYDRAULIC TEST as well.

      Refer to HYDRAULIC TEST [10/2017 - 09/2020]

      HINT: 

      The pressure values in Active Test and HYDRAULIC TEST are different from each other.

      OK

      The line pressure changes as specified when performing the Active Test.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE SHIFT SOLENOID VALVE SLT. Refer to  COMPONENTS [04/2013 - ] 

    Result: 

    OK 

    See step  4

  4. CHECK IF DTC OUTPUT RECURS 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [10/2017 - ]

      Powertrain > Transmission > Clear DTCs 

    5. Perform the Monitor Drive Pattern for ECT Test.

      Refer to MONITOR DRIVE PATTERN [10/2017 - ]

    6. Enter the following menus: Powertrain / Transmission / Trouble Codes.

      Powertrain > Transmission > Trouble Codes 

    7. Read the DTCs using the Techstream.

      Result

      Result Proceed to
      DTC P0781-00 is not output A
      DTC P0781-00 is output B

    Result: 

    A 

    END 

    Result: 

    B 

    REPAIR OR REPLACE AUTOMATIC TRANSMISSION WITH TRANSFER ASSEMBLY. Refer to  COMPONENTS [04/2013 - 09/2020] 

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