AUTOMATIC TRANSMISSION SYSTEM, Diagnostic DTC:P0741, P2757

DTC Code DTC Name
P0741 Torque Converter Clutch Solenoid Performance (Shift Solenoid Valve SL)
P2757 Torque Converter Clutch Pressure Control Solenoid Performance (Shift Solenoid Valve SLU)

DESCRIPTION

Based on the on and off signals of the shift solenoid valve SL, the TCM controls the fluid pressure to the lock-up relay valve, and turns lock-up on or off.

DTC Code

DTC Detection Condition


  1. Diagnosis Condition

  2. Malfunction Status

  3. Malfunction Time

  4. Other

 Trouble Area
P0741

  1. ECT is 40°C (104°F) or higher, ATF temperature is -10°C (14°F) or higher, and the vehicle is driven with the shift lever in D (no malfunctions are detected in shift solenoid valve SL1, 2, 3, 4 and 5, SR, SLU, SL, speed sensors (SP2, NT), engine coolant temperature sensor, oil temperature sensor, knock control sensor, electronic throttle, or CAN2)

  2. During a lock-up request, the engine speed and turbine speed slip amount is 70 rpm or more

  3. 2 seconds or more per trip

  4. 2 trip detection logic

  • Shift solenoid valve SL

  • Shift solenoid valve SLU

  • Valve body assembly

  • Torque converter clutch assembly

  • Automatic transmission assembly
P2757

  1. ECT is 40°C (104°F) or higher, ATF temperature is -10°C (14°F) or higher, and the vehicle is driven with the shift lever in D (no malfunctions are detected in shift solenoid valve SL1, 2, 3, 4 and 5, SR, SLU, SL, speed sensors (SP2, NT), engine coolant temperature sensor, oil temperature sensor, knock control sensor, electronic throttle, or CAN2)

  2. During a lock-up request, the engine speed and turbine speed slip amount is 70 rpm or more

  3. 2 seconds or more per trip

  4. 2 trip detection logic

  • Shift solenoid valve SL

  • Shift solenoid valve SLU

  • Valve body assembly

  • Torque converter clutch assembly

  • Automatic transmission assembly

MONITOR DESCRIPTION

Torque converter lock-up is controlled by the TCM based on the speed sensor (NT), engine speed, engine load, engine coolant temperature, vehicle speed, transmission fluid temperature, and gear selection. The TCM determines the lock-up status of the torque converter by comparing the engine speed (NE) to the input turbine speed (NT). The TCM calculates the actual transmission gear by comparing the input turbine speed (NT) to the counter gear speed (NC). When conditions are appropriate, the TCM requests "lock-up" by applying control voltage to shift solenoid SL. When shift solenoid SL is turned on, it applies pressure to the lock-up relay valve and locks the torque converter clutch.

If the TCM detects no lock-up after lock-up has been requested, the TCM interprets this as a fault in shift solenoid valve SL or SLU. The TCM will turn on the MIL and store the DTC.

Tech Tips

Example:

When the following condition is met, the system judges it to be a malfunction.

There is a difference in rotation between the input side (engine speed) and output side (input turbine speed) of the torque converter when the TCM commands lock-up (engine speed is at least 70 rpm more than the input turbine speed).

PROCEDURE


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


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the intelligent tester on.

    4. Enter the following menus: Powertrain / ECT / DTC.

    5. Read the DTCs using the intelligent tester.

      Result
      Display (DTC output) Proceed to
      Only P0741 and P2757 are output A
      P0741, P2757 and other DTCs are output B

      Tech Tips

      If a solenoid related or oil pressure switch related DTC is output, troubleshoot those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. INSPECT SHIFT SOLENOID VALVE SL AND SHIFT SOLENOID VALVE SLU


    1. A001FVSE01
      *1 Shift Solenoid Valve SL

      Check shift solenoid valve SL.


      1. Remove shift solenoid valve SL Click here.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Shift solenoid SL connector - Shift solenoid SL body 20°C (68°F) 11 to 15 Ω

      3. Connect the battery's positive (+) lead to the terminal of the solenoid valve connector, and the negative (-) lead to the solenoid body. Then check that the valve moves and makes an operating noise.

        OK
        Valve moves and makes operating noise.

    2. Check shift solenoid valve SLU.

      A0019VFE01
      *a Component without harness connected: (Shift Solenoid Valve SLU)

      1. Remove shift solenoid valve SLU Click here.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Terminal 1 of shift solenoid valve SLU - Terminal 2 20°C (68°F) 5.0 to 5.6 Ω

      3. Connect the battery's positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector. Then check that the valve moves and makes an operating noise.

        OK
        Valve moves and makes operating noise.
      Result
      Shift Solenoid Valve Condition Proceed to
      Shift solenoid valve SL and SLU are OK A
      Shift solenoid valve SL is NG B
      Shift solenoid valve SLU is NG C

    B

    REPLACE SHIFT SOLENOID VALVE SL Click here

    C

    REPLACE SHIFT SOLENOID VALVE SLU Click here

    A

  3. INSPECT TRANSMISSION VALVE BODY ASSEMBLY


    1. Check the transmission valve body assembly Click here.

      OK
      There are no foreign objects on any valve.

    NG

    REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY Click here

    OK

  4. INSPECT TORQUE CONVERTER CLUTCH ASSEMBLY


    1. Check the torque converter clutch assembly Click here.

      OK
      The torque converter clutch operates normally.

    OK

    REPAIR OR REPLACE AUTOMATIC TRANSMISSION ASSEMBLY Click here

    NG

    REPLACE TORQUE CONVERTER CLUTCH ASSEMBLY Click here