Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car's computer is saying that a part that helps control the pressure of the transmission fluid is stuck. It's like a valve that won't close properly, so the car might not change gears smoothly.
The transmission uses solenoids to control the flow of fluid, which helps change gears. If a solenoid is stuck, it can cause shifting problems.
The P0777 code indicates that the Powertrain Control Module (PCM) has detected a problem with the Pressure Control Solenoid B. Specifically, the solenoid is stuck in the 'on' position, affecting the transmission's ability to regulate hydraulic pressure.
• Harsh or delayed shifting
• Transmission slipping
• Check Engine Light illuminated
• Faulty pressure control solenoid B
• Transmission fluid issues (dirty or low)
• Wiring problems in the solenoid circuit
Solenoid: An electromechanical device that controls fluid flow in the transmission.
PCM: Powertrain Control Module, the car's computer that controls engine and transmission functions.
• Check the transmission fluid level and condition.
• Inspect the wiring and connectors to the solenoid.
• Test the solenoid for proper operation.
• Replace the faulty pressure control solenoid.
• Repair or replace damaged wiring or connectors.
• Flush and replace the transmission fluid.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $500
Moderate
• Nissan Altima
• Toyota Camry
• Honda Accord
• Regularly check and change the transmission fluid.
• Perform routine transmission maintenance.
• Inspect wiring for wear and tear.
Transmission Issue
• Avoid driving aggressively until the issue is fixed.
• Have the vehicle inspected by a professional mechanic.
Check if the vehicle's powertrain warranty covers transmission components.
This code has been commonly reported in vehicles with high mileage or those that have not had regular transmission maintenance.
Moderate – It should be addressed soon to prevent further transmission damage.
Driving with this issue may lead to unsafe driving conditions due to unpredictable gear shifts.
• Vehicle at operating temperature
• Transmission in drive mode
The pressure control solenoid is located inside the transmission, usually accessible by removing the transmission pan.
Q: Can I drive with a P0777 code?
A: It's not recommended to drive for long periods with this code, as it can lead to further transmission damage.
Q: How can I prevent this issue?
A: Regular maintenance of the transmission fluid and checking for any wiring issues can help prevent this problem.
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