AUTOMATIC TRANSMISSION SYSTEM (for 2TR-FE), Diagnostic DTC:P0796

DTC Code DTC Name
P0796 Pressure Control Solenoid "C" Performance (Shift Solenoid Valve SL3)

SYSTEM DESCRIPTION

The ECM uses the vehicle speed signal and signals from the transmission revolution sensors (NT, SP2) to detect the actual gear (1st, 2nd, 3rd, 4th, 5th or 6th gear).

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

DTC No. DTC Detection Condition Trouble Area
P0796

Either condition is met (2 trip detection logic):


  • The engine revs freely when a shift to 2nd or 6th gear is commanded.

  • The following condition is met twice:

    When a shift to 1st gear is commanded, 2nd gear is engaged.


  • Shift solenoid valve SL3 remains open or closed.

  • Transmission valve body assembly is blocked.

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

MONITOR DESCRIPTION

The ECM commands gear shifts by turning the shift solenoid valves on and off. According to the input turbine speed and output shaft speed, the ECM detects the actual gear (1st, 2nd, 3rd, 4th, 5th or 6th gear). When the gear commanded by the ECM and the actual gear are not the same, the ECM illuminates the MIL and stores the DTC.

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P0796)


    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 DTC P0796 is output A
      P0796 and other DTCs are output B

      Tech Tips

      If a solenoid is stuck off, DTCs for several solenoids including the malfunctioning solenoid will be detected.


    A
    B
  2. PERFORM ACTIVE TEST USING GTS (CONTROL THE SHIFT POSITION)

    Note

    This test should always be performed with at least 2 people.


    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 / Engine and ECT / Active Test.

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

      Tech Tips

      Comparing the gear commanded by the Active Test with the actual gear enables confirmation of the problem Click here.

      Engine and ECT
      Tester Display Test Part Control Range Diagnostic Note
      Control the Shift Position Operates the shift solenoid valves to allow gears to be selected manually.
      • Press "→" button: Up-shift occurs

      • Press "←" button: Down-shift occurs

      Can be used to check the operation of the shift solenoid valves.

      Up-shifts and down-shifts should be performed consecutively. A 10 seconds interval is required between gear changes.

      Do not down-shift at high speeds. Doing so will damage the automatic transmission.

      [Vehicle Condition]


      • 50 km/h (31 mph) or less

      Tech Tips


      • This test can be conducted when the vehicle speed is 50 km/h (30 mph) or less.

      • The 4th to 5th and 5th to 6th up-shift must be performed with the accelerator pedal released.

      • The 6th to 5th and 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 gear commanded by the ECM is shown in the Data List / Shift Status display on the GTS.

    8. Compare the ECM commanded gear and the actual gear.

      Result
      Actual Gear during Malfunction ECM Commanded Gear Proceed to
      1st 2nd 3rd 4th 5th 6th
      Shift solenoid valve SL1 Stuck ON 1st 2nd 3rd 4th 4th 4th A
      Stuck OFF N*1 N*1 N*1 N*1 5th 6th
      Shift solenoid valve SL2 Stuck ON 4th 4th 4th 4th 5th 6th B
      Stuck OFF 1st 2nd 3rd 1st N*1 N*1
      Shift solenoid valve SL3 Stuck ON 2nd 2nd 3rd 4th 5th 6th C
      Stuck OFF 1st 1st 3rd 4th 5th N*1
      Shift solenoid valve SL4 Stuck ON 3rd 3rd 3rd 4th 5th 5th D
      Stuck OFF 1st 2nd 1st 4th N*1 6th
      Shift solenoid valve SLT Stuck ON N*2 N*2 N*2 N*2 N*2 N*2 E
      Stuck OFF*3 1st 2nd 3rd 4th 5th 6th

      Tech Tips


      • *1: Neutral

      • *2: If shift solenoid valve SLT is stuck on, the line pressure will be low. Therefore, the amount of torque that can be transmitted by each gear is lower than the normal limit. When the engine power exceeds this lowered limit, the engine speed will increase freely.

      • *3: When shift solenoid valve SLT is stuck off, gear shifting is normal.


    B
    C
    D
    E
    A
  3. INSPECT SHIFT SOLENOID VALVE SL3


    1. B007WBKE25
      Text in Illustration
      *1 Shift Solenoid Valve SL3

      Remove shift solenoid valve SL3 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

    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.

    NG
    OK