CONTINUOUSLY VARIABLE TRANSAXLE SYSTEM, 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 Code

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. If there is an open or short in the oil pressure sensor circuit, the ECM detects the problem and stores the DTC.

WIRING DIAGRAM

C264274E35

CAUTION / NOTICE / HINT

Note:
  • Perform initialization when parts related to the continuously variable transaxle are replaced (Click here).

  • Check that no DTCs are stored after performing initialization (Click here).

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 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 more than once, make sure to wait 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.

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

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

      Table 1. 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:

      • 4.1 to 5.3 MPa (41.9 to 54.0 kgf/cm2, 594.5 to 768.5 psi): D position stall test

      • 4.3 to 5.3 MPa (43.9 to 54.0 kgf/cm2, 623.5 to 768.5 psi): R position stall test

      -

      Table 2. Result

      Result

      Proceed to

      Data display is not within Normal Condition range

      A

      Data display is within Normal Condition range

      B

    REPLACE ECMClick here

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

    1. Disconnect the C108 oil pressure sensor connector.

    2. Disconnect the C111 ECM connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      C108-1 (E2) - C111-109 (EPTO)

      Always

      Below 1 Ω

      C108-2 (PTO) - C111-79 (PTO)

      Always

      Below 1 Ω

      C108-3 (VC) - C111-110 (VCPT)

      Always

      Below 1 Ω

      C108-1 (E2) or C111-109 (EPTO) - Body ground and other terminals

      Always

      10 kΩ or higher

      C108-2 (PTO) or C111-79 (PTO) - Body ground and other terminals

      Always

      10 kΩ or higher

      C108-3 (VC) or C111-110 (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

      Switch Condition

      Specified Condition

      C111-79 (PTO) - Body ground

      Ignition switch ON

      Below 1 V

      C108-2 (PTO) - Body ground

      Ignition switch ON

      Below 1 V

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

  3. CHECK ECM (VCPT TERMINAL VOLTAGE)

    1. U122611E02

      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

      C108-3 (VC) - C108-1 (E2)

      Ignition switch ON

      4.75 to 5.25 V

      Table 3. Text in Illustration

      *a

      Front view of wire harness connector

      (to Oil Pressure Sensor)

    REPLACE ECMClick here

  4. REPLACE OIL PRESSURE SENSOR

    1. Replace the oil pressure sensor (Click here).

    PERFORM INITIALIZATION

  5. REPLACE ECM

    1. Replace the ECM (Click here).

    PERFORM INITIALIZATION

  6. REPLACE ECM

    1. Replace the ECM (Click here).

    PERFORM INITIALIZATION