P0777
DTC P0776 or P0777 (Gen 2 with 2.4L - LEA)
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 Solenoid Valve 2 Stuck Off
DTC P0777
- Pressure Control Solenoid Valve 2 Stuck On
Circuit/System Description
The clutch pressure control solenoid 2 is part of the Control Solenoid Valve Assembly which has no serviceable components. PC solenoid 2 regulates transmission fluid pressure to the 3-5-R regulator valve which controls pressure to the 3-5-R clutch. The transmission control module (TCM) calculates gear ratio based on the speed signals from the input shaft speed (ISS) sensor and the output shaft speed (OSS) sensor, The TCM compares the expected transmission gear ratio to the calculated gear ratio for each commanded gear.
Conditions for Running the DTC
P0776
* DTC P0101, P0102, P0103, P0106, P0107, P0108, P0171, P0172, P0174, P0175, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0401, P042E, P0716, P0717, P0722, P0723, or P182E is not set.
* Engine speed is 400-7500 RPM for 5 seconds.
* Ignition voltage is 9-32 V.
* Transmission fluid temperature (TFT) is -6.7°C (20°F) or greater.
* Transmission output speed is 100 RPM or greater, or the throttle position is 0.5 percent or greater.
* Throttle position signal is valid.
* High side driver is enabled.
P0777
* DTC P0101, P0102, P0103, P0106, P0107, P0108, P0171, P0172, P0174, P0175, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0401, P042E, P0716, P0717, P0722, P0723, or P182E is not set.
* Engine speed is 400-7500 RPM for 5 seconds.
* Ignition voltage is 9-32 V.
* Transmission fluid temperature is -6.7°C (20°F) or greater.
* Transmission output shaft speed is 100 RPM or greater, or the throttle position is 0.5 percent or greater.
* Throttle position signal is valid.
* High side driver is enabled.
* Throttle position is 10 percent or greater and the engine torque is 45 Nm (33 lb ft) or greater.
Conditions for Setting the DTC
P0776
* The TCM detects an incorrect on-coming clutch gear ratio, or flare, when the 3-5-R clutch is commanded ON for 3 seconds.
* The transmission input shaft speed is 400 RPM or greater from the anticipated input shaft speed.
* The conditions listed above must occur 3 times.
P0777
* The TCM detects an incorrect off-going clutch gear ratio, or tie-up, when the 3-5-R clutch is commanded OFF for 1 second.
* The transmission input shaft speed is 400 RPM or less from the anticipated input shaft speed.
* The conditions listed above must occur 3 times.
Action Taken When the DTC Sets
P0776
* DTC P0776 is a Type A DTC.
* TCM commands maximum line pressure.
* TCM freezes transmission adaptive functions.
* TCM inhibits TAP Up/TAP Down function.
* TCM inhibits manual shifting of forward gears.
* TCM inhibits powertrain braking.
* TCM inhibits auto grade braking.
* TCM inhibits neutral idle.
* TCM commands 2nd gear if the transmission is in a forward gear and the output speed is less than 700 RPM.
* TCM commands neutral if the output speed is 700 RPM or greater.
P0777
* DTC P0777 is a Type A DTC.
* TCM commands maximum line pressure.
* TCM limits the transmission to reverse and 3rd gear.
* TCM freezes transmission adaptive functions.
* TCM inhibits TAP Up/TAP Down function.
* TCM inhibits manual shifting of forward gears.
* TCM inhibits neutral idle.
* TCM inhibits powertrain braking.
* TCM inhibits auto grade braking.
Conditions for Clearing the DIC/DTC
DTCs P0776 and P0777 are Type A DTCs.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics Electrical Diagrams
Connector End View Reference
* Component Connector End Views Outside Rearview Mirror - Driver
* Inline Harness Connector End Views X100
Description and Operation
* Transmission General Description Transmission General Description
* Transmission Component and System Description Transmission Component and System Description
* Drive Range, Third Gear (Gen 2/Hybrid) Drive Range, Third Gear (Gen 2/Hybrid)
* Drive Range - Fourth Gear (Gen 2/Hybrid) Drive Range - Fourth Gear (Gen 2/Hybrid)
* Drive Range, Fifth Gear (Gen 2/Hybrid) Drive Range, Fifth Gear (Gen 2/Hybrid)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Special Tools
* DT-48616 - Solenoid Assembly Test Kit & Adapter Harness
* J 21867 - Pressure Gauge
For equivalent regional tools, refer to Special Tools Tools and Equipment.
Circuit/System Verification
Warning: Refer to Parking Brake and Drive Wheels Warning Parking Brake and Drive Wheels Warning.
1. Ignition ON, engine OFF.
2. Verify DTC P0716, P0717, P0722, P0723, P077C, P077D, P07BF, or P07C0 was not set by reviewing the scan tool Freeze Frame/Failure Records data.
• If a DTC was set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
• If a DTC is not set
3. Engine idling in Park, with parking brake applied and drive wheels chocked.
4. Verify the transmission fluid level and condition is correct. Refer to Transmission Fluid Level and Condition Check Transmission Fluid Level and Condition Check.
5. Ignition ON, clear the TCM DTCs with a scan tool.
6. Verify DTC P0776 or P0777 does not set while performing a road test. Refer to Road Test Initial Inspection and Diagnostic Overview.
• If DTC P0776 or P0777 sets
Refer to Circuit/System Testing.
• If DTC does not set
7. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
8. Verify the DTC does not set.
• If a DTC sets
Refer to Circuit/System Testing.
• If a DTC does not set
9. All OK
Circuit/System Testing
Note: You must perform the Circuit/System Verification first.
1. Engine idling at the normal operating temperature.
2. Verify the transmission line pressures are within the specified range. Refer to Line Pressure Check Line Pressure Check and Solenoid Valve Pressure (Gen 1) Solenoid Valve Pressure (Gen 1)Solenoid Valve Pressure (Gen 2 with 2.4L - LEA) Solenoid Valve Pressure (Gen 2 with 2.4L - LEA).
• If the pressures are not within range
Refer to Fluid Pressure High or Low Fluid Pressure High or Low.
• If the pressures are within range
3. Ignition OFF, remove the Q8 Control Solenoid Valve Assembly.
4. Verify a pressure change occurs when performing the solenoid test. Refer to Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test.
• If a pressure change does not occur
Replace the Q8 Control Solenoid Valve Assembly.
• If a pressure change occurs
5. Repair or replace as necessary.
DTC P0776 or P0777 - Control Valve Body Assembly
* Actuator feed limit circuit supply fluid to solenoids restricted or not available - debris or sediment blockage.
* 3-5-R Regulator Valve stuck/sticking - debris, binding, damaged valve, or scored bore.
* Control valve body ball check valve not seating correctly - debris.
DTC P0776 - 3-5-R and 4-5-6 Clutch Housing Assembly
3-5-R clutch backing plate retaining ring not seated, causing clutch pack over-travel.
DTC P0776 or P0777 - Torque Converter (w/Fluid Pump) Housing Assembly
Fluid pump housing/gear damaged/scored.
DTC P0776 - Channel Plate and Spacer Plate
Oil channels or orifices blocked by debris.
DTC P0776 or P0777 - Q8 Control Solenoid Valve Assembly
* Clutch Pressure Control Solenoid 2 stuck ON/OFF.
* O-ring seals leaking.
* Valve body filter plate assembly cracked, blocked, or damaged gasket seal.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Perform the Transmission Adaptive Values Learn Programming and Relearning following all transmission repairs.
* Control Solenoid Valve and Transmission Control Module Assembly Replacement Service and Repair
* Control Module References Control Module References for control solenoid valve assembly replacement, programming and setup.