Diagnostic Fault Information

WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

The components are listed from the least to the most intrusive to service.

Component	DTC	Condition
Q8 Control Solenoid Valve Assembly	P0776, P0777	Q27B Pressure Control Solenoid Valve 2 - Binding or Sticking/Stuck Control Solenoid Valve Assembly Filter Plate - Blocked by debris/Restricted or Cracked O-Ring - Leaking
Control Valve Body	P0776, P0777	Clutch Regulator Valve - Binding or Sticking/Stuck Control Valve Body Ball Check Valve - Leaking or Blocked by debris Oil Channels or Orifices - Blocked by debris/Restricted
Control Valve Body Spacer Plate	P0776	Oil Channels or Orifices - Blocked by debris/Restricted
Control Valve Channel Plate	P0776	Oil Channels or Orifices - Blocked by debris/Restricted
3-5-R and 4-5-6 Clutch Housing Assembly	P0776	3-5-R Clutch Backing Plate Retaining Ring - Not seated correctly 3-5-R clutch plates worn or damaged. Clutch Housing - Scored/Worn Clutch Piston Cracked Damaged seal.
Torque Converter with Fluid Pump Housing Assembly	P0776, P0777	Oil Pump Drive Gear - Worn Oil Pump Driven Gear - Worn Transmission Fluid Pump Housing - Scored/Worn