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

By turning the shift solenoid valve SL ON or OFF, the TCM controls the fluid pressure to the lock-up relay valve, turning the lock-up ON or OFF.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0741 Torque Converter Clutch Solenoid Performance (Shift Solenoid Valve DSL)

All of the following conditions are met (2 trip detection logic)


  • Engine coolant temperature is 40°C (104°F) or more

  • ATF temperature is -10°C (14°F) or more

  • 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, transmission revolution sensors (SP2, NT), water temperature sensor, oil temperature sensor, knock control sensor, electronic throttle, or CAN

  • During lock-up request, the engine speed and turbine speed slip amount is 70 rpm or more for 2 seconds


  • Shift solenoid valve SL

  • Shift solenoid valve SLU

  • Valve body assembly

  • Torque converter assembly

  • Automatic transmission assembly

Comes on DTC stored
P2757 Torque Converter Clutch Pressure Control Solenoid Performance (Shift Solenoid Valve SLU)

All of the following conditions are met (2 trip detection logic)


  • Engine coolant temperature is 40°C (104°F) or more

  • ATF temperature is -10°C (14°F) or more

  • 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, transmission revolution sensors (SP2, NT), water temperature sensor, oil temperature sensor, knock control sensor, electronic throttle, or CAN

  • During lock-up request, the engine speed and turbine speed slip amount is 70 rpm or more for 2 seconds


  • Shift solenoid valve SL

  • Shift solenoid valve SLU

  • Valve body assembly

  • Torque converter assembly

  • Automatic transmission assembly

Comes on DTC stored

MONITOR DESCRIPTION

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

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

Tech Tips

Example:

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

There is a difference in rotation (speed) 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 greater than the input turbine speed.)

CAUTION / NOTICE / HINT

Note

Perform registration and/or initialization when parts related to the automatic transmission are replaced.

Click here

Tech Tips

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


  1. Perform the D Position Shift Test in Road Test.

    Click here

  2. Turn the engine switch off.

  3. Perform step (1) again.

  4. Check for DTCs again.

    Click here

PROCEDURE


  1. CHECK DTC OUTPUT


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

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


      Powertrain > ECT > Trouble Codes
    5. Read the DTCs using the GTS.

      Result
      Result Proceed to
      Only DTCs 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 that DTC first.


    B
    A
  2. INSPECT SHIFT SOLENOID VALVE SL


    1. Remove the shift solenoid valve SL.

      Click here

    2. B002CUTC01
      *a Shift Solenoid Valve SL

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Terminal of shift solenoid valve SL connector - Shift solenoid valve SL body 20°C (68°F) 11 to 15 Ω
    3. Connect a positive (+) lead from the battery to the terminal of the solenoid valve connector, and a negative (-) lead to the solenoid body. Check that the valve moves and makes an operating sound.

      OK
      Valve moves and makes an operating sound.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  3. INSPECT SHIFT SOLENOID VALVE SLU


    1. B002E4SC46
      *a

      Component without harness connected

      (Shift Solenoid Valve SLU)

      Remove the 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 the shift solenoid valve SLU - Terminal 2 20°C (68°F) 5.0 to 5.6 Ω
    3. Connect a positive (+) lead from the battery with a 21 W bulb to terminal 2 and a negative (-) lead to terminal 1 of the solenoid valve connector. Check that the valve moves and makes an operating sound.

      OK
      Valve moves and makes an operating sound.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  4. INSPECT TRANSMISSION VALVE BODY ASSEMBLY


    1. Check the transmission valve body assembly.

      Click here

      OK
      There is no foreign matter on each valve and they operate smoothly.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  5. INSPECT TORQUE CONVERTER ASSEMBLY


    1. Check the torque converter assembly.

      Click here

      OK
      The torque converter operates normally.
      Result
      Proceed to
      OK
      NG

    OK
    NG