Toyota Corolla Cross: Pressure Control Solenoid "B" Actuator Stuck Off (P07757F)

DESCRIPTION

Using the current from the TCM, the shift solenoid valve SL2 controls the C2 clutch pressure in accordance with the requested shift mode.

When the TCM requests the shift mode to be changed to belt mode, the C2 clutch is engaged and the input torque is transmitted to the output shaft via the steel belt.

MONITOR DESCRIPTION

• When the TCM requests the shift mode to be changed to belt mode, the shift solenoid valve SL2 is turned ON and the C2 clutch is engaged. As a result, the transmission revolution sensor (NSS) signal becomes equal to the transmission revolution sensor (NOUT) signal.

  By comparing the signals indicating the secondary pulley revolution (speed) and output shaft revolution (speed), the TCM judges if the shift mode is belt mode or not.

  When the TCM requests the shift mode to be changed to belt mode, if the difference between the transmission revolution sensor (NSS) and (NOUT) signals is more than 300 rpm, it determines the shift solenoid valve SL2 is malfunctioning, illuminates the MIL and stores this DTC.

• Under normal conditions, when the TCM requests the shift mode to be changed to gear mode, line pressure is applied from the shift solenoid SL1 to engage the C1 clutch and gear mode is entered.

  When the shift solenoid valve SL2 is stuck ON, if the TCM requests the shift mode to be changed to gear mode, line pressure is applied to the clutch apply control valve from the shift solenoid valve SL2 and in turn line pressure to the C1 clutch is blocked.

  As a result, the C1 clutch cannot be engaged and the shift mode cannot be changed.

  In this case, when the TCM requests the shift mode to be changed to gear mode, it detects that gear mode cannot be entered (the C1 clutch is not engaged and the difference between the transmission revolution sensor (NT) signal and transmission revolution sensor (NC1) signal exceeds the threshold) and determines that the shift solenoid valve SL2 is stuck ON, illuminates the MIL and stores a DTC.

  SL2 Stuck ON Detection Condition:

  *A	TCM commands C1 clutch engagement when shift solenoid valve SL2 normal	*B	TCM commands C1 clutch engagement when shift solenoid valve SL2 stuck ON
  *1	Shift Solenoid Valve SL1	*2	Shift Solenoid Valve SL2
  *3	Clutch Apply Control Valve	*4	C1 Clutch
  *a	Shift solenoid valve SL2 stuck ON	-	-
  	Oil Pressure Flow		Valve Movement

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

• Any of the following conditions are met: OFF malfunction (A) and (B) or (A) and (C) OFF malfunction (A)

  TCM indicate belt mode clutch	Engagement
  l Secondary sheave speed - Output speed l	More than 300 rpm

  OFF malfunction (B) (after OFF malfunction (A) is met)

  TCM indicate gear mode clutch	Engagement
  l Turbine Speed - Gear mode clutch speed l	Less than 25 rpm

  OFF malfunction (C) (after OFF malfunction (A) is met)

  Shift solenoid valve SLP	Operating belt mode clutch control by TCM command
  Secondary sheave speed - Output speed	Less than 25 rpm

• All of the following conditions are met: ON malfunction (A), (B) and (C) ON malfunction (A)

  TCM indicate gear mode clutch	Engagement
  l Turbine Speed - Gear mode clutch speed l	More than 200 rpm

  ON malfunction (B) (after ON malfunction (A) is met)

  Target clamping pressure	1.4 MPa (14.3 kgf/cm2, 203 psi) or more
  l Actual clamping pressure - Target clamping pressure l	Less than 0.5 MPa (5.1 kgf/cm2, 73 psi)

  ON malfunction (C) (after ON malfunction (A) and (B) are met)

  TCM indicate belt mode clutch	Engagement
  l Secondary sheave speed - Output speed l	Less than 25 rpm

CONFIRMATION DRIVING PATTERN

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

HINT:

• After repairs have been completed, clear the DTCs and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
• When clearing the permanent DTCs, refer to the Clear Permanent DTC procedure.

  Click here

1. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
2. Turn the ignition switch off and wait for 2 minutes or more.
3. Turn the ignition switch to ON and turn the GTS on.
4. Start the engine.
5. Perform the D Position Shift Test inspection in Road Test. [*1]

   Click here

   HINT:

   [*1]: Normal judgment procedure.

   The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

6. Stop the vehicle.
7. Enter the following menus: Powertrain / Transmission / Utility / All Readiness.
8. Input the DTC: P07757F.
9. Check the DTC judgment result.

   GTS Display	Description
   NORMAL	DTC judgment completed System normal
   ABNORMAL	DTC judgment completed System abnormal
   INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions
   N/A	Unable to perform DTC judgment Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

   HINT:

   • If the judgment result shows NORMAL, the system is normal.
   • If the judgment result shows ABNORMAL, the system has a malfunction.
   • If the judgment result shows INCOMPLETE or N/A, perform the normal judgment procedure again.

CAUTION / NOTICE / HINT

NOTICE:

• Perform the universal trip to clear permanent DTCs.

  Click here

• Perform registration and/or initialization when parts related to the continuously variable transaxle system are replaced.

  Click here

• Check that no DTCs are stored after performing initialization.

  Click here

HINT:

If any DTCs other than P07757F are output, perform troubleshooting for those DTCs first.

PROCEDURE

(a) Enter the following menus:

(b) Read the DTCs using the GTS.

HINT:

• If DTC P077512 or P077514 is output, perform troubleshooting for that DTC first.
• If DTCs P077512 and P077514 are not output but DTC P281F00 is output, perform troubleshooting for DTC P281F00 first.

B

GO TO STEP 5

C

GO TO DTC CHART (DTC P077512)

D

GO TO DTC CHART (DTC P077514)

E

GO TO DTC CHART (DTC P281F00)

F

GO TO DTC CHART

A

(a) Disconnect the transmission wire connector from the shift solenoid valve SL2.

Click here

(b) Connect a positive (+) lead from the auxiliary battery with a 21 W bulb to terminal 1 and a negative (-) lead to terminal 2 of the shift solenoid valve SL2 connector. Check that the valve moves and makes an operating sound.

OK:

Valve moves and makes an operating sound.

NG

GO TO STEP 4

OK

Click here

NEXT

PERFORM REGISTRATION AND INITIALIZATION for Registration: Click here for Initialization: Click here

Click here

NEXT

PERFORM REGISTRATION AND INITIALIZATION for Registration: Click here for Initialization: Click here

(a) Disconnect the transmission wire connector from the shift solenoid valve SL1.

Click here

(b) Connect a positive (+) lead from the auxiliary battery with a 21 W bulb to terminal 1 and a negative (-) lead to terminal 2 of the shift solenoid valve SL1 connector. Check that the valve moves and makes an operating sound.

OK:

Valve moves and makes an operating sound.

OK

GO TO STEP 2

NG

Click here

NEXT

PERFORM REGISTRATION AND INITIALIZATION for Registration: Click here for Initialization: Click here

READ NEXT: