CONTINUOUSLY VARIABLE TRANSAXLE SYSTEM, Diagnostic DTC:P0741, P075B, P2757

DTC Code DTC Name
P0741 Torque Converter Clutch Solenoid Performance (Shift Solenoid Valve SL)
P075B Shift Solenoid "G" Performance or Stuck Off
P2757 Torque Converter Pressure Control Solenoid Circuit Stuck OFF / Performance (SLU / DSU Solenoid)

DESCRIPTION

The ECM uses the shift solenoid valves SC and SL to switch control of the shift solenoid valve SLU between forward and reverse clutch control and lock-up control in response to driving conditions.

Tech Tips

If DTC P0741 is stored after the engine has stalled, the lock-up shift solenoid valve (shift solenoid valve SL) may be malfunctioning.

DTC No.

DTC Detection Condition


  1. Diagnosis Condition

  2. Malfunction Status

  3. Malfunction Time

  4. Other

 Trouble Area
P0741

  1. The ECM sends a lock-up OFF command and turns the shift solenoid valves SC and SL OFF.

  2. The difference between the engine speed (NE) and the transmission revolution sensor (NT) speed is 25 rpm or less.

  3. 1 second or more

  4. 2 trip detection logic

  • Torque converter assembly

  • Continuously variable transaxle assembly

  1. The ECM turns the shift solenoid valves SC and SL ON.

  2. The difference between the transmission revolution sensor (NT) speed and the transmission revolution sensor (NIN) speed is 300 rpm or more.

  3. 1 second or more

  4. 2 trip detection logic

  1. The vehicle is being driven.

  2. The lock-up ON command is sent, but lock-up control is not performed.

  3. 1 second or more

  4. 2 trip detection logic
P075B

  1. The ECM turns the shift solenoid valves SC and SL OFF.

  2. The difference between the transmission revolution sensor (NT) speed and the transmission revolution sensor (NIN) speed is 300 rpm or more.

  3. 0.3 second or more

  4. 2 trip detection logic

  • Torque converter assembly

  • Continuously variable transaxle assembly

  1. The vehicle is being driven.

  2. The lock-up ON command is sent, but lock-up control is not performed.

  3. 1 second or more

  4. 2 trip detection logic

  1. The ECM sends a lock-up ON command and turns the shift solenoid valves SC and SL ON.

  2. The difference between the engine speed (NE) and the transmission revolution sensor (NT) speed is 25 rpm or less.

  3. 1 second or more

  4. 2 trip detection logic
P2757

  1. The ECM sends a lock-up ON command, and turns the shift solenoid valves SC and SLU OFF and SL ON.

  2. The difference between the engine speed (NE) and the transmission revolution sensor (NT) speed is 25 rpm or less.

  3. 1 second or more

  4. 2 trip detection logic

  • Torque converter assembly

  • Continuously variable transaxle assembly

  1. The vehicle is being driven.

  2. The lock-up signal is on, but the lock-up is off

  3. 1 second or more

  4. 2 trip detection logic

MONITOR DESCRIPTION

When performing lock-up control (on/off) of the torque converter, the ECM compares the input turbine speed (NT) and engine speed (NE) to detect mechanical malfunctions in the shift solenoid valves SL and SC.

If the torque converter does not lock-up while a lock-up ON command is being sent, the ECM detects a mechanical malfunction in the shift solenoid valve SLU.

When the rotating speeds are different, the ECM detects the problem, illuminates the MIL and stores these DTCs.

PROCEDURE


  1. CHECK DTC OUTPUT (IN ADDITION TO DTC P0741, P075B AND P2757)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    5. Read the DTCs using the GTS.

      Result
      Result Proceed to
      Only P0741, P075B and/or P2757 is output A
      P0741, P075B and/or P2757 and other DTCs are output B

      Tech Tips

      If any other DTCs besides P0741, P075B or P2757 are output, perform troubleshooting for those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. CLEAR DTC


    1. Clear the DTC Click here.


    NEXT

  3. PERFORM DRIVE TEST

    CAUTION:

    Strictly observe posted speed limits, traffic laws and road conditions when performing the road 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.

    Tech Tips


    • Lock-up control will not operate when the CVT fluid temperature is 40°C (104°F) or less and the vehicle speed is 60 km/h (37 mph) or less, or when the CVT fluid temperature is 5°C (41°F) or less.

    • Lock-up control will not operate when the engine coolant temperature is 40°C (104°F) or less.

    • The lock-up off vehicle speed may vary depending on the electrical load, and air conditioning and brake operations.


    1. Connect the GTS to the DLC3.

    2. Start the engine.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Engine Speed, SPD (NT), SPD (NIN), Lock Up, SL Solenoid Status and Solenoid (SC).

    5. Check the Data List while driving.

      Engine and ECT
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Engine Speed

      Engine speed/

      Min.: 0 rpm, Max.: 16383 rpm

      		 550 to 650 rpm: Idling When the crankshaft position sensor is malfunctioning, "Engine Speed" is approximately 0 rpm or varies greatly from the actual engine speed.
      SPD (NT)

      Input turbine speed/

      min.: 0 rpm

      max.: 12750 rpm

      • Input turbine speed (NT) equal to engine speed(NE): Lock-up ON (After warming up engine)

      • Input turbine speed (NT) nearly equal to engine speed(NE): Lock-up OFF (Idling with shift lever in P or N)

      • 0 rpm: Vehicle stopped with shift lever in D

      		 Data is displayed in increments of 50 rpm.
      SPD (NIN)

      Primary pulley speed (NIN)/

      min.: 0 rpm

      max.: 12750 rpm

      • 0 rpm: Vehicle stopped

      • Primary pulley speed (NIN) equal to engine speed(NE): Lock-up ON (After warming up engine)

      		 Data is displayed in increments of 50 rpm.
      Lock Up

      Lock-up/

      OFF or ON

      • ON: Lock-up operating

      • OFF: Lock-up not operating

      		 -
      SL Solenoid Status

      Shift solenoid valve SL status/

      OFF or ON

      • OFF: Ignition switch ON

      • ON: After engine start

      		 -
      Solenoid (SC)

      Shift solenoid valve SC status/

      OFF or ON

      • OFF: Ignition switch ON

      • ON: After engine start

      		 -
      Result
      Result Proceed to
      When the lock-up condition is ON, the input turbine speed (NT) is lower than the engine speed (NE). A
      When the shift solenoid valves SC and SL are OFF, the input turbine speed (NT) is equal to the engine speed (NE).
      When the shift solenoid valves SC and SL are ON, there is a large difference between the input turbine speed (NT) and the primary pulley speed (NIN).
      When the lock-up condition is ON, the input turbine speed (NT) is equal to the engine speed (NE). B
      When the shift solenoid valves SC and SL are OFF, the input turbine speed (NT) is lower than the engine speed (NE).
      When the shift solenoid valves SC and SL are ON, the input turbine speed (NT) is equal to the primary pulley speed (NIN).

    B

    CHECK INTERMITTENT PROBLEMS Click here

    A

  4. REPLACE CONTINUOUSLY VARIABLE TRANSAXLE ASSEMBLY AND TORQUE CONVERTER ASSEMBLY


    1. Replace the continuously variable transaxle assembly 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