Diagnostic article Generic OBD-II
P0776: CVT primary-pulley pressure fails to follow a high command
P0776 is pressure-control solenoid B performance/stuck off.
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Documented application
Documented monitors in gm-2025-03a, model year 2025. These are module/calibration examples; vehicle, engine and transmission applicability must be confirmed independently.
The code alone does not identify a failed part or establish that a vehicle is safe to drive. Confirm the vehicle, reporting module and applicable service procedure.
P0776 is pressure-control solenoid B performance/stuck off. The cited TCM example explicitly applies to a CVT primary-pulley pressure actuator, with low measured primary pressure despite a high functional command.
A pressure response test, not a winding test
The displayed criterion is raw primary-pulley pressure below 200 kPa for more than three seconds after the diagnostic is enabled. Without the high-command context, a low pressure measurement does not establish the documented fault. Conversely, a valid electrical command does not prove that hydraulic pressure followed it.
The source calls this an actuator performance monitor. It does not determine from this row alone whether the actuator, another hydraulic element or the measurement path is responsible, and it does not prescribe solenoid replacement.
Check the prerequisites before judging a pass
The monitor requires adequate battery voltage and excludes pending or active primary-speed and output-speed faults. Fast-learn, solenoid-cleaning and line-pressure-adaptation states also appear among the inhibiting conditions. Pressure behavior during those special functions should not be interpreted as ordinary enabled operation.
Keep the requested pressure, measured primary pressure and service-mode status together in the diagnostic record. Verification should show an appropriate commanded response and a completed passing monitor using the exact CVT service process. The explicit primary-pulley mapping is specific to this source; the generic solenoid-B label does not establish the same hardware location in another transmission.
Source and applicability
Documented monitors in gm-2025-03a, model year 2025. These are module/calibration examples; vehicle, engine and transmission applicability must be confirmed independently. GM 2025-03a, page 1116.
Article source documents
Source checks describe how the text was prepared; they do not certify a diagnosis or confirm compatibility with every vehicle using this code.
Original code reference
Dictionary definition
Pressure Control Solenoid B Performance/Stuck Off
This definition retains its original catalog scope. The article above is limited to its explicitly documented application.
Reference scope
Generic OBD-II definition.
A manufacturer label does not establish the model, year, engine or module to which a diagnosis applies. Read the safety and diagnostic limits.
Definition source
- DTC Database: pinned community code definitions
Source checked · MIT