СИСТЕМА АВТОМАТИЧЕСКОЙ ТРАНСМИССИИ, Diagnostic DTC:P0746, P0771

DTC Code DTC Name
P0746 Pressure Control Solenoid "A" Performance (Shift Solenoid Valve SL1)
P0771 Shift Solenoid "E" Performance (Shift Solenoid Valve SR)

DESCRIPTION

The TCM uses signals from the transmission revolution sensor (NT) and transmission revolution sensor (SP2) to detect the actual gear position (1st, 2nd, 3rd, 4th or 5th gear).

Then the TCM compares the actual gear with the shift schedule in the TCM memory to detect mechanical problems with the shift solenoid valves, valve body or automatic transmission (clutch, brake, gear, etc.).

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0746 Pressure Control Solenoid "A" Performance (Shift Solenoid Valve SL1) The gear required by the TCM does not match the actual gear when driving (2-trip detection logic).
  • Shift solenoid valve SL1 remains closed

  • Shift solenoid valve SR remains open or closed

  • Shift solenoid valve SLT remains open or closed

  • Valve body is blocked

  • Automatic transmission (clutch, brake, gear, etc.)

- DTC stored
P0771 Shift Solenoid "E" Performance (Shift Solenoid Valve SR) The gear required by the TCM does not match the actual gear when driving (1-trip detection logic).
  • Shift solenoid valve SR remains open or closed

  • Shift solenoid valve SL1 remains closed

  • Shift solenoid valve SLT remains open or closed

  • Valve body is blocked

  • Automatic transmission (clutch, brake, gear, etc.)

- DTC stored

MONITOR DESCRIPTION

These DTCs indicate a stuck ON malfunction or stuck OFF malfunction of shift solenoid valves SR and SL1.

The TCM commands gear shifts by turning the shift solenoid valves ON/OFF. When the gear position commanded by the TCM and the actual gear position are not the same, the TCM stores the DTC.

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.


    for P0746:

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

    Click here

  2. Turn the ignition switch off.

  3. Perform step (*1) again.

  4. Check for DTCs again.

    Click here


    for P0771:

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

    Click here

  2. Check for DTCs again.

    Click here


  1. ACTIVE TEST

    Tech Tips

    Using the GTS to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests.


    1. Warm up the engine.

    2. Turn the ignition switch off.

    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 / ECT / Active Test.

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

      Tech Tips

      While driving, the shift position can be forcibly changed with the GTS.

      Comparing the shift position commanded by the Active Test with the actual shift position enables you to confirm the problem.

      Click here


      Powertrain > ECT > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Control the Shift Position Operate shift solenoid valves and set each shift position
      • Press "→" button: Shift up

      • Press "←" button: Shift down

      Possible to check operation of the shift solenoid valves.

      [Vehicle Condition]

      50 km/h (31 mph) or less


      Powertrain > ECT > Active Test
      Active Test Display
      Control the Shift Position
      Data List Display
      Shift Status

      Tech Tips


      • This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.

      • The 4th to 5th up-shift must be performed with the accelerator pedal released.

      • The 5th to 4th down-shift must be performed with the accelerator pedal released.

      • Do not operate the accelerator pedal for at least 2 seconds after shifting and do not shift successively.

      • The shift position commanded by the TCM is shown in the Data List display on the GTS.

      • Shift solenoid valves SL1 and SR are turned ON/OFF normally when the shift lever is in D.

        TCM gear shift command 1st 2nd 3rd 4th 5th
        Shift solenoid valve SL1 OFF OFF OFF OFF ON
        Shift solenoid valve SR OFF OFF OFF OFF ON

PROCEDURE


  1. CHECK DTC OUTPUT (IN ADDITION TO DTCS P0746 AND P0771)


    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 / ECT / Trouble Codes.


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

      Result
      Result Proceed to

      • Only P0746 and P0771 are output

      • Only P0771 is output

      A
      P0746, P0771 and other DTCs are output B

      Tech Tips

      If any other codes besides P0746 and P0771 are output, perform troubleshooting for those DTCs first.


    B
    A
  2. PERFORM ACTIVE TEST USING GTS (SHIFT SOLENOID VALVE SLT)

    Note


    • Perform the test while the ATF temperature is between 50 and 80°C (122 and 176°F).

    • Be careful to prevent the hose of SST from interfering with the exhaust pipe.

    • Perform the test with the air conditioning off.

    Tech Tips

    Using the GTS to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests.


    1. A01SEYFE01

      Remove the test plug from the transmission case and connect SST.

      SST
      09993-19015   ( 09993-00010, 09993-00040 )
    2. Connect the GTS to the DLC3.

    3. Start the engine and warm it up.

    4. Measure the line pressure with SST.

    5. Turn the GTS on.

    6. Enter the following menus: Powertrain / ECT / Active Test.

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

    8. Measure the line pressure.


      Powertrain > ECT > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Activate the Solenoid (SLT) Operate shift solenoid valve SLT and raise line pressure

      ON or OFF

      Tech Tips


      • OFF: Line pressure up (when Active Test "Activate the Solenoid (SLT)" is performed, TCM commands shift solenoid valve SLT to turn OFF)

      • ON: No action (normal operation)

      [Vehicle Condition]


      • Vehicle stopped

      • Engine idling


      Powertrain > ECT > Active Test
      Tester Display
      Activate the Solenoid (SLT)

      The "Activate the Solenoid (SLT)" in the Active Test is performed to check the line pressure changes by connecting SST to the automatic transmission, which is used in the Hydraulic Test as well.

      Click here

      Tech Tips

      Note that the pressure values in the Active Test and Hydraulic Test are different.

      OK
      The line pressure changes as specified when performing the Active Test.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  3. INSPECT SHIFT SOLENOID VALVE SL1


    1. A01SK10C22
      *a

      Component without harness connected

      (Shift Solenoid Valve SL1)

      Remove shift solenoid valve SL1.

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 - 2 20°C (68°F) 5.0 to 5.6 Ω
    3. Apply 12 V battery voltage to the shift solenoid valve and check that the valve moves and makes an operating noise.

      OK
      Measurement Condition Specified Condition

      • Battery positive (+) with a 21 W bulb → Terminal 1

      • Battery negative (-) → Terminal 2

      Valve moves and makes an operating noise
      Result
      Proceed to
      OK
      NG

    NG
    OK
  4. INSPECT SHIFT SOLENOID VALVE SR


    1. A01SDILC07
      *a

      Component without harness connected

      (Shift Solenoid Valve SR)

      Remove shift solenoid valve SR.

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Shift solenoid valve SR connector terminal - Shift solenoid valve SR body 20°C (68°F) 11 to 15 Ω
    3. Apply 12 V battery voltage to the shift solenoid valve and check that the valve moves and makes an operating noise.

      OK
      Measurement Condition Specified Condition

      • Battery positive (+) → Shift solenoid valve SR connector

      • Battery negative (-) → Shift solenoid valve SR body

      Valve moves and makes operating noise
      Result
      Proceed to
      OK
      NG

    NG
    OK
  5. INSPECT TRANSMISSION VALVE BODY ASSEMBLY


    1. Check the transmission valve body assembly.

      Click here

      OK
      There are no foreign objects on any valve.
      Result
      Proceed to
      OK
      NG

    OK
    NG