CONTINUOUSLY VARIABLE TRANSAXLE SYSTEM, Diagnostic DTC:P0842, P0843

DTC Code DTC Name
P0842 Transmission Fluid Pressure Sensor/Switch "A" Circuit Low
P0843 Transmission Fluid Pressure Sensor/Switch "A" Circuit High

DESCRIPTION

The ECM performs learning control for the belt clamping pressure, based on the belt clamping pressure signal, which is detected by the oil pressure sensor.

DTC No.

DTC Detection Condition


  1. Diagnosis Condition

  2. Malfunction Status

  3. Malfunction Time

  4. Other

 Trouble Area
P0842

  1. 2 seconds or more after engine start

  2. Short in oil pressure sensor circuit

  3. 0.5 seconds

  4. 1 trip detection logic

  • Wire harness or connector

  • Oil pressure sensor

  • ECM
P0843

  1. 2 seconds or more after engine start

  2. Open or short to B+ in oil pressure sensor circuit

  3. 0.5 seconds

  4. 1 trip detection logic

  • Wire harness or connector

  • Oil pressure sensor

  • ECM

MONITOR DESCRIPTION

These DTCs indicate an open or short in the oil pressure sensor. When there is an open or short circuit in oil pressure sensor circuits, the ECM detects the problem and stores the DTC.

WIRING DIAGRAM

A005GOQE30
*a Oil Pressure Sensor

PROCEDURE


  1. READ VALUE USING GTS (A/T OIL PRESSURE)

    CAUTION:

    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 the test with the A/C off.

    • Do not perform the stall speed test for longer than 5 seconds.


    1. Fully apply the parking brake and chock the 4 wheels.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Start the engine.

    5. Turn the GTS on.

    6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Connect the TC and TE1.

    7. Enter the following menus: Powertrain / Engine and ECT / Data List.

    8. In accordance with the display on the GTS, read the Data List.

      Engine and ECT
      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


      • 0.2 to 2.2 MPa (2 to 22.4 kgf/cm2, 29 to 319 psi): Engine idling (Vehicle stopped with shift lever in N)

      • 4.0 to 4.8 MPa (40.8 to 48.9 kgf/cm2, 580 to 696 psi): D position stall test

      		 -
      Result
      Result Proceed to
      Data displayed is not within Normal Condition range A
      Data displayed is within Normal Condition range B

    B

    REPLACE ECM Click here

    A

  2. CHECK HARNESS AND CONNECTOR (OIL PRESSURE SENSOR - ECM)


    1. Disconnect the oil pressure sensor connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)
      Tester Connection Condition Specified Condition
      B45-1 (E2) - B23-121 (EPTO) Always Below 1 Ω
      B45-2 (PTO) - B23-89 (PTO) Always Below 1 Ω
      B45-3 (VC) - B23-120 (VCPT) Always Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      B45-1 (E2) or B23-121 (EPTO) - Body ground and other terminals Always 10 kΩ or higher
      B45-2 (PTO) or B23-89 (PTO) - Body ground and other terminals Always 10 kΩ or higher
      B45-3 (VC) or B23-120 (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
      B23-89 (PTO) - Body ground Ignition switch ON Below 1 V
      B45-2 (PTO) - Body ground Ignition switch ON Below 1 V

    5. Connect the ECM connector.

    6. Connect the oil pressure sensor connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK ECM (VCPT TERMINAL VOLTAGE)


    1. A005I0DE02
      Text in Illustration
      *a

      Front view of wire harness connector:

      (to Oil Pressure Sensor)

      Disconnect the oil pressure sensor connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      B45-1 (E2) - B45-3 (VC) Ignition switch ON 4.75 to 5.25 V

    NG

    REPLACE ECM Click here

    OK

  4. REPLACE OIL PRESSURE SENSOR


    1. Replace the oil pressure sensor Click here.


    NEXT

  5. PERFORM INITIALIZATION

    Note


    • Performing reset memory/initialization will clear the learned value of the deceleration sensor (deceleration sensor zero point calibration) and the CVT oil pressure (CVT oil pressure calibration). Make sure to perform reset memory, deceleration sensor zero point calibration, and CVT oil pressure calibration when replacing any of the parts shown in the following table:

      Replaced Part

      • Continuously variable transaxle assembly

      • ECM

      • Brake actuator assembly (Skid control ECU)

      • Oil pressure sensor

      • Deceleration sensor

    • After reset memory, always perform deceleration sensor (deceleration sensor zero point) calibration first, and then the CVT oil pressure calibration.

    • Always perform the zero point calibration with the vehicle on level ground.

    • Do not shake or vibrate the vehicle during the zero point calibration.


    1. Using the GTS, perform the reset memory, deceleration sensor zero point calibration and CVT oil pressure calibration Click here.

    2. Check for DTCs again Click here.


    NEXT

    END

  6. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

  7. PERFORM INITIALIZATION

    Note


    • Performing reset memory/initialization will clear the learned value of the deceleration sensor (deceleration sensor zero point calibration) and the CVT oil pressure (CVT oil pressure calibration). Make sure to perform reset memory, deceleration sensor zero point calibration, and CVT oil pressure calibration when replacing any of the parts shown in the following table:

      Replaced Part

      • Continuously variable transaxle assembly

      • ECM

      • Brake actuator assembly (Skid control ECU)

      • Oil pressure sensor

      • Deceleration sensor

    • After reset memory, always perform deceleration sensor (deceleration sensor zero point) calibration first, and then the CVT oil pressure calibration.

    • Always perform the zero point calibration with the vehicle on level ground.

    • Do not shake or vibrate the vehicle during the zero point calibration.


    1. Using the GTS, perform the reset memory, deceleration sensor zero point calibration and CVT oil pressure calibration Click here.

    2. Check for DTCs again Click here.


    NEXT

    END