CONTINUOUSLY VARIABLE TRANSAXLE SYSTEM(for 1ZR-FAE), Diagnostic DTC:P0842 and 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 output by the oil pressure sensor.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0842

Transmission Fluid Pressure Sensor/Switch "A" Circuit Low

1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other

  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

Comes on

DTC stored

P0843

Transmission Fluid Pressure Sensor/Switch "A" Circuit High

1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other

  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

Comes on

DTC stored

MONITOR DESCRIPTION

These DTCs indicate an open or short in the oil pressure sensor circuit. If there is an open or short in the oil pressure sensor circuit, the ECM detects the malfunction, illuminates the MIL and stores a DTC.

WIRING DIAGRAM

C318995E02

CAUTION / NOTICE / HINT

Tip:

After performing repair, clear the DTCs and perform the following procedure to check that DTCs are not output.

  1. Start the engine and wait for 2 seconds or more.

  2. Check for DTCs again.

    Click here

PROCEDURE

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

    CAUTION:

    A 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 performed after checking and confirming that the engine is normal.

    • Perform this test with the CVT fluid temperature between 50 and 100°C (122 and 212°F).

    • Perform this test with the air conditioning 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 GTS to the DLC3.

    4. Turn the ignition switch to ON.

    5. Turn the GTS on.

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

      Powertrain > Engine and ECT > Active Test

      Active Test Display

      Connect the TC and TE1

      Data List Display

      A/T Oil Pressure

    7. According to the display on the GTS, perform the Active Test.

    8. According to the display on the GTS, 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:

      • 2.8 to 4.8 MPa (28.5 to 49.0 kgf/cm2, 406 to 697 psi): D position stall test

      • 2.9 to 4.8 MPa (29.5 to 49.0 kgf/cm2, 420 to 697 psi): R position stall test

      -

    Result

    Result

    Proceed to

    Data List value is not normal

    A

    Data List value is normal

    B
    B

    REPLACE ECMClick here

    A

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

    1. Disconnect the B30 oil pressure sensor connector.

    2. Disconnect the B186 ECM connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      B30-1 (E2) - B186-109 (EPTO)

      Always

      Below 1 Ω

      B30-2 (PTO) - B186-79 (PTO)

      Always

      Below 1 Ω

      B30-3 (VC) - B186-110 (VCPT)

      Always

      Below 1 Ω

      B30-1 (E2) or B186-109 (EPTO) - Body ground and other terminals

      Always

      10 kΩ or higher

      B30-2 (PTO) or B186-79 (PTO) - Body ground and other terminals

      Always

      10 kΩ or higher

      B30-3 (VC) or B186-110 (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

      B186-79 (PTO) - Body ground

      Ignition switch ON

      Below 1 V

      B30-2 (PTO) - Body ground

      Ignition switch ON

      Below 1 V

    5. Connect the B186 ECM connector.

    6. Connect the B30 oil pressure sensor connector.

    Result

    Proceed to

    OK

    NG
    NG

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

    OK

  3. CHECK ECM (VCPT TERMINAL VOLTAGE)

    1. C125747C16

      *a

      Front view of wire harness connector

      (to Oil Pressure Sensor)

      Disconnect the B30 oil pressure sensor connector.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      B30-3 (VC) - B30-1 (E2)

      Ignition switch ON

      4.75 to 5.25 V

    3. Connect the B30 oil pressure sensor connector.

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE ECMClick here

    OK

  4. REPLACE OIL PRESSURE SENSOR

    1. Replace the oil pressure sensor.

      Click hereClick here

    Result

    Proceed to

    NEXT
    NEXT

    PERFORM INITIALIZATION

    Click here

  5. REPLACE ECM

    1. Replace the ECM.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    PERFORM INITIALIZATION

    Click here

  6. REPLACE ECM

    1. Replace the ECM.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    PERFORM INITIALIZATION

    Click here