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DTC P0842, P0843; Transmission Fluid Pressure Sensor/Switch "A" Circuit Low [08/2016 - ]: Procedure

  1. READ VALUE USING TECHSTREAM (A/T OIL PRESSURE) 
    WARNING:

    The stall speed test should always be performed with at least 2 people. One person should observe the condition of the wheels and wheel chocks while the other is performing the test.

    NOTE:
    • This test must be conducted after checking and confirming that the engine is operating normally.
    • Perform this test while the CVT fluid temperature is between 50 and 100°C (122 and 212°F).
    • Perform this test with the A/C off.
    • Do not perform the stall speed test for longer than 5 seconds
    • When performing the stall speed test repeatedly, wait for 15 seconds or more between tests.
    1. Warm up the engine.
    2. Fully apply the parking brake and chock all 4 wheels.
    3. Connect the Techstream to the DLC3.
    4. Turn the ignition switch to ON.
    5. Turn the Techstream on.
    6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Connect the TC and TE1.

      Powertrain > Engine and ECT > Active Test 

      Tester Display
      Connect the TC and TE1
    7. Enter the following menus: Powertrain / Engine and ECT / Data List / Primary.
    8. According to the display on the Techstream, read the Data List.

      Powertrain > Engine and ECT > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      A/T Oil Pressure Secondary oil pressure value min.: -64 MPa
      max.: 63.998 MPa      		 Secondary oil pressure inspection:
      except Destination Package for Mexico: 
      • for 2ZR-FE:
        • 3.5 to 4.8 MPa (35.7 to 48.9 kgf/cm2 , 508 to 696 psi): D position stall test
        • 3.6 to 4.8 MPa (36.7 to 48.9 kgf/cm2 , 522 to 696 psi): R position stall test
      • for 2ZR-FAE:
        • 3.6 to 4.8 MPa (36.7 to 48.9 kgf/cm2 , 522 to 696 psi): D position stall test
        • 3.7 to 4.8 MPa (37.7 to 48.9 kgf/cm2 , 537 to 696 psi): R position stall test

      for Destination Package for Mexico: 
      • for 2ZR-FAE:
        • 3.5 to 4.8 MPa (35.7 to 48.9 kgf/cm2 , 508 to 696 psi): D position stall test
        • 3.6 to 4.8 MPa (36.7 to 48.9 kgf/cm2 , 522 to 696 psi): R position stall test
      		 -

      Powertrain > Engine and ECT > Data List 

      Tester Display
      A/T Oil Pressure

      Result

      Result Proceed to
      Data List values are not normal A
      Data List values are normal B

    Result:  2

    B 

    See step  6

    Result:  1

    A 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (OIL PRESSURE SENSOR - ECM) 
    1. Disconnect the B29 oil pressure sensor connector.
    2. Disconnect the B33 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B29-1 (E2) - B33-121 (EPTO) Always Below 1 Ω
      B29-2 (PTO) - B33-89 (PTO) Always Below 1 Ω
      B29-3 (VC) - B33-120 (VCPT) Always Below 1 Ω
      B29-1 (E2) or B33-121 (EPTO) - Body ground and other terminals Always 10 kΩ or higher
      B29-2 (PTO) or B33-89 (PTO) - Body ground and other terminals Always 10 kΩ or higher
      B29-3 (VC) or B33-120 (VCPT) - Body ground and other terminals Always 10 kΩ or higher
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      B33-89 (PTO) - Body ground Ignition switch ON Below 1 V
      B29-2 (PTO) - Body ground Ignition switch ON Below 1 V
    5. Connect the B33 ECM connector.
    6. Connect the B29 oil pressure sensor connector.

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (OIL PRESSURE SENSOR - ECM) 

    Result:  1

    OK 

    See step  3

  3. CHECK ECM (VCPT TERMINAL VOLTAGE) 
    1. Disconnect the B29 oil pressure sensor connector.
      GTY454838Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Oil Pressure Sensor)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      B29-3 (VC) - B29-1 (E2) Ignition switch ON 4.75 to 5.25 V
    3. Connect the B29 oil pressure sensor connector.

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    See step  5

    Result:  1

    OK 

    See step  4

  4. REPLACE OIL PRESSURE SENSOR 
    1. Replace the oil pressure sensor.

      Refer to COMPONENTS [08/2013 - ]

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    PERFORM INITIALIZATION. Refer to  INITIALIZATION [08/2016 - ] 

  5. REPLACE ECM 
    1. Replace the ECM.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    PERFORM INITIALIZATION. Refer to  INITIALIZATION [08/2016 - ] 

  6. REPLACE ECM 
    1. Replace the ECM.

      Result

      Proceed to
      NEXT

    Result:  1

    NEXT 

    PERFORM INITIALIZATION. Refer to  INITIALIZATION [08/2016 - ] 

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