DTC Troubleshooting: P0777
DTC P0777: A/T Clutch Pressure Control Solenoid Valve B Stuck ON
NOTE:
Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review the General Troubleshooting Information.
If DTC P0777 is stored in the PCM, the transmission does not shift to any gear other than 3rd or 6th gear because of the fail-safe function.

DTC Description
Confirmed DTC
Pending DTC
Freeze Frame
P0777 A/T Clutch Pressure Control Solenoid Valve B Stuck ON
      

1.
ATF check:

ATF check
?1.
Warm up the engine to normal operating temperature (the radiator fan comes on).

?2.
Make sure that the transmission is filled to the proper level, and check for fluid leaks.

?3.
Drain the ATF through a strainer. Inspect the strainer for metal debris or excessive clutch material.

Does the strainer have metal debris or excessive clutch material?

     
YES
     
     
     
     
NO
     
     
     
Replace the ATF, then go to step 2.
2.
Problem verification:

Problem verification
?1.
Press the engine start/stop button to select the ON mode.

?2.
Clear the DTC with the HDS.


?3.
Start the engine.

?4.
With the brake pedal pressed, shift to D, and check the parameter(s) below with the HDS.
Signal
Current conditions
Values
Unit
3rd Pressure Switch
    
6th Pressure Switch
    

Does the 6th Pressure Switch turn on momentarily, then does the 3rd Pressure Switch turn on with a harsh shift?

     
YES
     
     
     
The failure is duplicated. Faulty A/T clutch pressure control solenoid valve B. Replace the secondary valve body (A/T clutch control solenoid valve B).?
     
NO
     
     
     
Intermittent failure, the system is OK at this time.?