P0777
DTC P0776 or P0777
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0776
- Pressure Control (PC) Solenoid 2 - Stuck OFF
DTC P0777
- Pressure Control (PC) Solenoid 2 - Stuck ON
Circuit/System Description
The clutch pressure control solenoid 2 is part of the control solenoid valve assembly and is not serviced separately. The clutch pressure control solenoid 2 controls transmission fluid pressure to the hybrid direct, 2-3-4 clutch regulator valve. The transmission control module monitors the transmission fluid pressure switch 3 state, in order to determine function of the clutch pressure control solenoid 2 and the hybrid direct, 2-3-4 clutch regulator valve. When the clutch pressure control solenoid 2 is commanded ON, the transmission fluid pressure switch 3 state should be High. When the clutch pressure control solenoid 2 is commanded Off, the transmission fluid pressure switch 3 parameter state should be Low.
Conditions for Running the DTC
P0776 or P0777
* The engine run time is greater than 1 second.
* Shift solenoid valve 1 is not in a transition state.
* The transmission line pressure is greater than 370 kPa (54 psi) and not fluctuating by greater than 30 kPa (4 psi).
* Propulsion is active.
P0776
The clutch pressure control solenoid 2 commanded pressure is greater than 1800 kPa (261 psi) for 4.5 seconds.
P0777
The clutch pressure control solenoid 2 commanded pressure is less than 5 kPa (1 psi) for 4.5 seconds.
Conditions for Setting the DTC
P0776 - Fail Case 1
The clutch pressure control solenoid 2 commanded pressure is 1800 kPa (261 psi) and the transmission fluid pressure switch 3 state is Low for 30 seconds.
P0776 - Fail Case 2
The clutch pressure control solenoid 2 commanded pressure is 1800 kPa (261 psi) and the transmission fluid pressure switch 3 state is Low for 0.5 seconds greater than 5 times during a key cycle.
P0777 - Fail Case 1
The clutch pressure control solenoid 2 commanded pressure is 5 kPa (1 psi) and the transmission fluid pressure switch 3 state is High for 36 seconds.
P0777 - Fail Case 2
The clutch pressure control solenoid 2 commanded pressure is 5 kPa (1 psi) and the transmission fluid pressure switch 3 state is High for 1.25 seconds greater than 5 times during a key cycle.
Action Taken When the DTC Sets
* P0776 and P0777 are Type B DTCs.
* The transmission control module commands maximum line pressure.
* The transmission control module freezes transmission adaptive functions.
Conditions for Clearing the DTC
P0776 and P0777 are Type B DTCs.
Diagnostic Aids
When attempting to set transmission performance DTCs, observe the Freeze Frame and Failure Records to assist in duplicating the failure conditions. With a scan tool, monitor the PC Sol. 2 Pressure Command and the TFP Switch 3 state parameters. Operate the vehicle in drive to obtain 72 km/h (45 mph) for at least 10 seconds, stop the vehicle, turn the ignition Off for at least 30 seconds. Perform this operation 2 times. When the PC Sol. 2 Pressure Command is Yes, the transmission fluid pressure switch 3 state should be high. When the PC Sol. 2 Pressure Command is No, the TFP switch 3 state should be Low.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics (Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Special Tools
DT-47825 Control Solenoid Test Plate
Component Testing
Circuit/System Verification
1. Verify that DTCs P0721, P0722, P0723, P0966, P0967, P0969, P0970, P0971, P0973, P0974, P0976, P0977, P2720, P2721, P2728, P2729, or P2730 are not set.
• If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle).
2. Perform the Transmission Fluid Level and Condition Check (Transmission Fluid Level and Condition Check) procedure.
3. Perform the Line Pressure Check (Line Pressure Check) procedure.
• If the pressure is out of specification, correct this concern first.
4. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (Control Solenoid Valve and Transmission Control Module Assembly Inspection).
• If a concern is found, repair or replace the control solenoid valve assembly.
5. Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test (Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test).
• If the solenoid is found to be leaking or stuck closed, replace the control solenoid valve assembly.
6. Inspect the control valve lower body assembly for sticking valves, damage, scored bores, or debris.
• If a concern is found in the valve body, repair or replace the valve body as necessary.
7. Inspect the hybrid direct, 2-3-4 clutch assembly for damage.
• If a concern is found in the hybrid direct, 2-3-4 clutch assembly, repair or replace as necessary.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Control Solenoid Valve and Transmission Control Module Assembly Replacement (Control Solenoid Valve and Transmission Control Module Assembly Replacement) for control valve assembly removal.
* Control Valve Assembly Disassemble (54. Control Valve Assembly Disassemble) for control valve assembly inspection and overhaul.
* Hybrid Direct, 2-3-4 Clutch Housing Overhaul (29. Hybrid Direct, 2-3-4 Clutch Housing Overhaul) for hybrid direct, 2-3-4 clutch assembly replacement.
* Control Module References (Programming and Relearning) for control solenoid valve assembly replacement, setup, and programming.