Engine-Codes.com
Engine-Codes – GMC – P0777 GMC

P0777 GMC Code - Clutch Pressure Control Solenoid 2 Stuck On

Quick Answer

The P0777 code in a GMC vehicle indicates an issue with the Clutch Pressure Control Solenoid 2 being stuck on. Common causes include Malfunctioning Clutch Pressure Control Solenoid 2, Electrical faults in the solenoid circuit, Debris blocking solenoid movement. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means
P0777 GMC indicates Clutch Pressure Control Solenoid 2 Stuck On.
Common causes
Common causes include Malfunctioning Clutch Pressure Control Solenoid 2, Electrical faults in the solenoid circuit, Debris blocking solenoid movement.
Severity
High - diagnose this code as soon as possible.
Can I drive?
Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
What is this?
Table of contents Created and updated by William Orellana on Sep 08, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0777 GMC Description

The P0777 code in a GMC vehicle indicates an issue with the Clutch Pressure Control Solenoid 2 being stuck on. This solenoid is responsible for regulating the hydraulic pressure in the transmission's clutch system, which is crucial for proper gear shifting and overall transmission function. When the solenoid is stuck in the "on" position, it can lead to various performance issues and potentially cause long-term damage to the transmission if not addressed promptly.

OBDII Code P0777 GMC - Clutch Pressure Control Solenoid 2 Stuck On
P0777 GMC Code - Clutch Pressure Control Solenoid 2 Stuck On

Common Causes of P0777 GMC

  1. Malfunctioning Clutch Pressure Control Solenoid 2
  2. Electrical faults in the solenoid circuit
  3. Debris blocking solenoid movement
  4. Low or contaminated transmission fluid
  5. Wiring issues or connection problems

Symptoms of P0777 GMC

  1. Harsh or delayed shifting
  2. Slipping gears
  3. Poor acceleration
  4. Decreased fuel efficiency
  5. Transmission overheating

How to Fix P0777 GMC

  1. Begin by diagnosing the specific cause of the issue using a scan tool to read the fault codes and perform a transmission fluid check.
  2. Inspect the Clutch Pressure Control Solenoid 2 and its wiring for any visible damage or blockages, then replace or repair as needed.
  3. Flush and refill the transmission fluid if it is low or contaminated, ensuring the correct type and level are used.
  4. Clear the fault codes from the vehicle's computer system and test drive the vehicle to verify the repair and ensure proper transmission operation.
  5. If the issue persists, further inspection by a professional technician may be required to identify any underlying transmission problems that could be contributing to the solenoid malfunction.

Cost to Fix P0777 GMC

The typical repair costs for addressing a P0777 code in a GMC vehicle can vary depending on the specific cause of the issue and the extent of the repair needed. In general, replacing a faulty Clutch Pressure Control Solenoid 2 and addressing any related issues can range from $200 to $500 for parts and labor. However, it's important to note that diagnosis time and labor rates at auto repair shops can vary based on location, vehicle make and model, and engine type. Rates typically range from $80 to $150 per hour, with metropolitan areas or dealerships potentially charging higher rates, while independent shops may offer lower prices. To obtain a more precise estimate, it's recommended to consult local auto repair shops for accurate pricing.

What does this mean?

Tech Notes for P0777 GMC

When a transmission solenoid has malfunctioned, in most cases the problem is not the electrical part of the solenoid; the problem is foreign material obstructing the mechanical function of the solenoid or the flow of the fluid through the transmission valve body. If the transmission fluid is dirty, it's recommended to change the transmission fluid and if possible, remove the transmission pan for further diagnosis. Excessive debris or metal particles on the transmission pan could be an indication that there is a mechanical transmission failure, and that the transmission will need to be rebuilt or replaced.

There is a factory service bulletin for the following GMC Models:
2007-2009 GMC Acadia
2007-2009 GMC Acadia Factory Service Bulletin OBDII Code P0777

Need more information about the P0777 GMC code?

Need more information on how to fix the P0777 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0777 GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0777 GMC Code

No Frequently Asked Questions about P0777 GMC Code found.

Discuss the causes and fixes for P0777 GMC OBDII Code

Submit a New Comment

  • I have a '07 Acadia with 140 k miles, I had the transmission fluid exchange service on it. After service I could hear a high pitched sound in first gear.200 miles later it began to slip and 300 miles later transmission went completely out.It know shows PO 777 and P2723 codes. I know GMC has extened the warranty on this particular transmission. What do you think caused the transmission to go out? Something with the fluid
    Exchange or just a coenicidence.

    Reply to Comment