AUTOMATIC TRANSAXLE SYSTEM, Diagnostic DTC:P07757F

DTC Code DTC Name
P07757F Pressure Control Solenoid "B" Actuator Stuck Off

SYSTEM DESCRIPTION

The ECM uses the vehicle speed signal and signals from the transmission speed sensors (NC, NT) 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 malfunctions of the shift solenoid valves and transmission valve body assembly.

DTC No. DTC Detection Condition Trouble Area
P07757F

1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other


    DTC Detection Condition 1:

  1. ATF temperature is -10°C (14°F) or more, and the vehicle is being driven with the shift lever in D (no malfunctions are detected in the shift solenoid valves (SL1, SL2, SL3 and SL4), transmission revolution sensor (NT, NC), coolant temperature sensor, oil temperature sensor, knock control sensor, electronic throttle, or CAN2)

  2. When the ECM commands the transaxle to shift to 4th, 5th or 6th gear, the engine overruns.

  3. 0.5 seconds

  4. 2-trip detection logic


    DTC Detection Condition 2:

  1. ATF temperature is -10°C (14°F) or more, and the vehicle is being driven with the shift lever in D (no malfunctions are detected in the shift solenoid valves (SL1, SL2, SL3 and SL4), transmission revolution sensor (NT, NC), coolant temperature sensor, oil temperature sensor, knock control sensor, electronic throttle, or CAN2)

  2. When the ECM commands the transaxle to shift to 1st, 2nd or 3rd gear, the actual gear is shifted to 4th.

  3. 0.8 seconds

  4. 2-trip detection logic

  • Shift solenoid valve SL2 remains open or closed

  • Transmission valve body assembly is blocked

  • Automatic transaxle assembly (clutch, brake, gear, etc.)

MONITOR DESCRIPTION

The ECM commands gear shifts by turning the shift solenoid valves on and off. According to the input shaft revolution (speed), intermediate (counter) shaft revolution (speed) and output shaft revolution (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 a DTC.

CAUTION / NOTICE / HINT

Note

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

Tech Tips

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


  1. Perform the D Position Shift Test inspection 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 OTHER DTCS OUTPUT (IN ADDITION TO DTC P07757F)


    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 / Transmission / Trouble Codes.

    5. Read the DTCs using the GTS.

      Result
      Result Proceed to
      Only DTC P07757F is output A
      DTC P07757F and other DTCs are output B

      Tech Tips

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


    A

    INSPECT SHIFT SOLENOID VALVE SL2 Click here

    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 engine switch off.

    3. Connect the GTS to the DLC3.

    4. Turn the engine switch on (IG).

    5. Turn the GTS on.

    6. Enter the following menus: Powertrain / Transmission / Active Test / Control the Shift Position.

    7. Perform the Active Test according to the display on the GTS.

      Tech Tips

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

      Transmission
      Tester Display Test Details Control Range Diagnostic Note
      Control the Shift Position Operates the shift solenoid valves to allow gears to be selected manually

      • Press "→" button: Upshift occurs

      • Press "←" button: Downshift occurs

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

      Upshifts and downshifts should be performed consecutively. A 10-second interval is required between gear changes.

      Do not downshift at high speeds. Doing so will damage the automatic transaxle.

      [Vehicle Condition]

      50 km/h (31 mph) or less

      Note


      • This Active Test can be performed when the vehicle is stopped.

      • When shifting gears using the Active Test, do not operate the accelerator pedal for 2 seconds before and after shifting gears.

      Tech Tips

      The gear commanded by the ECM is shown in the Data List / Shift Status display on the GTS.

    8. Check the vehicle speed and gear when the engine speed is 1000 rpm.

      Tech Tips

      As the torque converter clutch has not engaged, it may be difficult to obtain the speeds specified for 4th, 5th, and 6th gear, however a difference of speed should still be evident following each gear change.

      Standard
      1st 2nd 3rd 4th 5th 6th

      8 to 12 km/h

      (5 to 7 mph)

      15 to 19 km/h

      (9 to 12 mph)

      21 to 25 km/h

      (13 to 16 mph)

      31 to 35 km/h

      (19 to 22 mph)

      44 to 48 km/h

      (27 to 30 mph)

      52 to 56 km/h

      (32 to 35 mph)

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

      Result
      Actuator 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 the 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 will be lower than the normal limit. When the engine power exceeds this limit, the engine speed will increase freely.

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


    A

    GO TO DTC CHART (DTC P07457F) Click here

    C

    GO TO DTC CHART (DTC P07957F) Click here

    D

    GO TO DTC CHART (DTC P28077F) Click here

    E

    GO TO DTC CHART (DTC P27137F) Click here

    B

  3. INSPECT SHIFT SOLENOID VALVE SL2


    1. A01W2VBE46
      Text in Illustration
      *1 Shift Solenoid Valve SL2

      Remove the shift solenoid valve SL2.

    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. 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.

    NG

    REPLACE SHIFT SOLENOID VALVE SL2 Click here

    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.

    OK

    REPAIR OR REPLACE AUTOMATIC TRANSAXLE ASSEMBLY Click here

    NG

    REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY Click here