DTC P0776: Pressure Control Solenoid "B" Performance/Stuck Off: Notes

1. - 

DTC detecting condition: 

Detected when two consecutive driving cycles with fault occur.

Trouble symptom: 

• Engine speed increases abruptly, and cannot accelerate.
• Excessive slippage is felt.

Wiring diagram: 

CVT control system Ref. to WIRING SYSTEM>CVT CONTROL SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK DTC  .

   Read the DTC using Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Besides DTC P0776, is any of the DTC P0717, P0966, P0967 or P2747 displayed?

   Yes  : Perform the diagnosis according to DTCs other than P0776. Ref. to TRANSMISSION (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST .

   No  : Go to  2 .

2. CHECK F&R SOLENOID (ACTIVE TEST)  .
   1. Turn the ignition switch to ON.
   2. Using the Subaru Select Monitor, perform the active test for F&R solenoid. Ref. to TRANSMISSION (DIAGNOSTICS)>ACTIVE TEST .

   Does the indication of 0 → 500 mA appear repeatedly during the active test, and does operating sound emit during indicating 500 mA?

   Yes  : Go to  5 .

   No  : Go to  3 .

3. CHECK F&R SOLENOID  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the TCM connector.
   3. Measure the resistance between TCM connector and transmission body.

   Connector & terminal 

   (T10) No. 16 - Transmission body:

   Is the resistance approximately 3.5 - 7.1 Ω? (When cold)

   Yes  : Go to  7 .

   No  : Go to  4 .

4. CHECK HARNESS  .

   Check the transmission harness. (Open circuit, short circuit to power supply, short circuit to ground, and poor contact)

   Is the check result OK?

   Yes  : Go to  7 .

   No  : Repair the harness.

5. CHECK TRANSMISSION FLUID  .
   1. Connect the TCM connector.
   2. Check the amount of ATF. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CVTF>INSPECTION .

   Is the check result OK?

   Yes  : Go to  6 .

   No  : Adjust the amount of ATF. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CVTF>INSPECTION .

6. CHECK TRANSMISSION FLUID  .

   Check the condition of ATF. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CVTF>REPLACEMENT .

   Is the check result OK?

   Yes  : Return ATF. Go to  7 .

   No  : Check according to the "Corrective action" of ATF (CVTF) "CONDITION CHECK". Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CVTF>REPLACEMENT .

7. CHECK INPUT SIGNAL FOR TCM  .
   1. Lift up the vehicle.
   2. Start the engine.
   3. Warm up until the ATF temperature reaches to 40 - 70°C (104 - 158°F).
   4. Depress the brake pedal, and shift the select lever to "D" range.
   5. Shift the select lever to "P" range.
   6. Stabilize the engine speed at idle.
   7. Read the data of [Actual Secondary Pressure] using Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DATA MONITOR .

   Is [Actual Secondary Pressure] 0.5 - 1.5 MPa?

   Yes  : Go to  8 .

   No  : Perform the diagnosis according to DTC P0841. Ref. to TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P0841: TRANSMISSION FLUID PRESSURE SENSOR/SWITCH "A" CIRCUIT RANGE/PERFORMANCE .

8. STALL TEST  .

   Perform the stall test. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>STALL TEST .

   Is the result of the stall test OK?

   Yes  : Go to  9 .

   No  : Replace the transmission assembly if the stall speed is higher than the standard value of the stall test. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>TRANSMISSION ASSEMBLY .

9. CHECK BY INSPECTION MODE  .
   1. Using the Subaru Select Monitor, perform the clear memory. Ref. to COMMON (DIAG)>CLEAR MEMORY .
   2. Execute the inspection mode. Ref. to TRANSMISSION (DIAGNOSTICS)>INSPECTION MODE . Does the AT OIL TEMP light blink and is DTC P0776 displayed?

   Yes  : Replace the transmission assembly. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>TRANSMISSION ASSEMBLY .

   No  : Current condition is normal. It is possible that temporary poor contact occurs.