AUTOMATIC TRANSAXLE SYSTEM, Diagnostic DTC:P07957F

DTC Code DTC Name
P07957F Pressure Control Solenoid "C" Actuator Stuck Off

DESCRIPTION

Based on signals from the transmission revolution sensors (NT, NC3 and NC), the actual gear is detected.

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

Tech Tips

Actual gear when shift solenoid valve SL3 (without fail-safe control) malfunction occurs:
ECM commanded gear 1st 2nd 3rd 4th 5th 6th 7th 8th
Actual gear during SL3 stuck ON malfunction 3rd 3rd 3rd 3rd 7th 7th 7th 7th
Actual gear during SL3 stuck OFF malfunction 1st 2nd N (1st)* 4th 5th 6th N* 8th

*: Neutral

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory Note
P07957F Pressure Control Solenoid "C" Actuator Stuck Off

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


    SL3 stuck ON malfunction:

  1. Engine coolant temperature is 40°C (104°F) or higher, ATF temperature is -10°C (14°F) or higher, and the vehicle is being driven with the shift lever in D (no malfunctions are detected in the shift solenoid valves SL1, SL2, SL3, SL4, SL5 and S1, transmission revolution sensors (NT, NC3, NC), coolant temperature sensor, oil temperature sensor, knock control sensor, electronic throttle or CAN2)

  2. One of the following occurs:


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

    2. When the ECM commands the transaxle to shift to 5th, 6th or 8th gear, the actual gear changes to 7th gear.

  3. Malfunction status continues for 0.6 seconds or more

  4. 2-trip detection logic


    SL3 stuck OFF malfunction:

  1. Engine coolant temperature is 40°C (104°F) or higher, ATF temperature is -10°C (14°F) or higher, and the vehicle is being driven with the shift lever in D (no malfunctions are detected in the shift solenoid valves SL1, SL2, SL3, SL4, SL5 and S1, transmission revolution sensors (NT, NC3, NC), coolant temperature sensor, oil temperature sensor, knock control sensor, electronic throttle or CAN2)

  2. When the ECM commands the transaxle to shift to 3rd or 7th gear, the engine overruns (neutral status).

  3. Malfunction status continues for 0.5 seconds or more

  4. 2-trip detection logic

  • Shift solenoid valve S1

  • Shift solenoid valve SLT

  • Shift solenoid valve SL1

  • Shift solenoid valve SL2

  • Shift solenoid valve SL3

  • Shift solenoid valve SL4

  • Shift solenoid valve SL5

  • Transmission valve body assembly

  • Torque converter assembly

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

 Comes on DTC stored

SAE Code:

P0796

MONITOR DESCRIPTION

The ECM commands gear shifts by turning the shift solenoid valves on and off. According to the input shaft revolution (speed), C3 clutch drum revolution (speed) and output shaft revolution (speed), the ECM detects the actual gear (1st, 2nd, 3rd, 4th, 5th, 6th, 7th or 8th 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 DTC OUTPUT (IN ADDITION TO DTC P07957F)


    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.


      Powertrain > Transmission > Trouble Codes

    5. Read the DTCs using the GTS.

      Result
      Result Proceed to
      DTC P07957F and DTC P07457F, P07507E, P07757F, P27137F, P28077F and/or P28167F are output A
      Only DTC P07957F is output B
      DTC P07457F, P07507E, P07757F, P07957F, P27137F, P28077F, P28167F and other DTCs are output C

      Tech Tips


      • If any DTCs other than P07457F, P07507E, P07757F, P07957F, P27137F, P28077F and P28167F are output, perform troubleshooting for those DTCs first.

      • If a shift solenoid valve is stuck ON or OFF, DTCs for several shift solenoid valves including the malfunctioning shift solenoid valve will be stored.


    B

    GO TO STEP 3 Click here

    C

    GO TO DTC CHART Click here

    A

  2. CLEAR DTC AND PERFORM STALL SPEED TEST


    1. Clear the DTCs.

      Click here

      Tech Tips

      Write down the currently output DTCs before clearing them.


      Powertrain > Transmission > Clear DTCs

    2. Perform the stall speed test.

      Click here

      Result
      Test Condition Proceed to
      Stall speed test can be performed A
      Stall speed test cannot be performed B

    B

    GO TO STEP 5 Click here

    A

  3. INSPECT SHIFT SOLENOID VALVE SL1, SL2, SL3, SL4 AND SL5


    1. B007XRMC67
      *a

      Component without harness connected

      (Shift Solenoid Valve SL1, SL2, SL3, SL4 and SL5)

      Remove the shift solenoid valves SL1, SL2, SL3, SL4 and SL5.

      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 SL1 connector terminal 1 - terminal 2 20°C (68°F) 5.0 to 5.6 Ω
      Shift solenoid valve SL2 connector terminal 1 - terminal 2 20°C (68°F) 5.0 to 5.6 Ω
      Shift solenoid valve SL3 connector terminal 1 - terminal 2 20°C (68°F) 5.0 to 5.6 Ω
      Shift solenoid valve SL4 connector terminal 1 - terminal 2 20°C (68°F) 5.0 to 5.6 Ω
      Shift solenoid valve SL5 connector terminal 1 - terminal 2 20°C (68°F) 5.0 to 5.6 Ω

    3. Connect a positive (+) lead from the battery to terminal 1 and a negative (-) lead with a 21 W bulb to terminal 2 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

    REPLACE SHIFT SOLENOID VALVE SL1, SL2, SL3, SL4 OR SL5 Click here

    OK

  4. INSPECT SHIFT SOLENOID VALVE S1


    1. A01VWNRC01
      *1 Shift Solenoid Valve S1

      Remove the shift solenoid valve S1.

      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 S1 connector terminal - Shift solenoid valve S1 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

    REPLACE SHIFT SOLENOID VALVE S1 Click here

    OK

  5. INSPECT SHIFT SOLENOID VALVE SLT


    1. B007XRMC67
      *a

      Component without harness connected

      (Shift Solenoid Valve SLT)

      Remove the shift solenoid valve SLT.

      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 SLT connector terminal 1 - terminal 2 20°C (68°F) 5.0 to 5.6 Ω

    3. Connect a positive (+) lead from the battery to terminal 1 and a negative (-) lead with a 21 W bulb to terminal 2 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

    REPLACE SHIFT SOLENOID VALVE SLT Click here

    OK

  6. INSPECT TRANSMISSION VALVE BODY ASSEMBLY


    1. Inspect 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

    REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY Click here

    OK

  7. INSPECT TORQUE CONVERTER ASSEMBLY


    1. Inspect the torque converter assembly.

      Click here

      OK
      The torque converter assembly is normal.
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE TORQUE CONVERTER ASSEMBLY Click here

    OK

  8. REPAIR OR REPLACE AUTOMATIC TRANSAXLE ASSEMBLY


    1. Repair or replace the automatic transaxle assembly.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    PERFORM A/T CODE REGISTRATION Click here