Diagnostic article Generic OBD-II
P287C: Invalid transmission learn data at initialization
P287C can reflect invalid stored clutch, pressure or synchronizer adaptation data checked when the controller initializes.
Read before applying this article
Documented application
2025 GM 07A-2 documented monitor only; module and calibration applicability must be matched to the vehicle. The application-matrix filename join remains unresolved; no model or engine fitment is inferred.
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.
P287C is often described as transmission adaptive values not learned. In this GM table, the controller checks the validity of transmission learn data at initialization. The code therefore concerns the stored information used to control the transmission, rather than directly declaring that one clutch slipped during a road test.
The data has several independent parts
The listed checks cover both factory end-of-line information and values learned during operation. Examples include clutch preload and kiss-point pressure, fill-volume information, pressure-to-current correction and sensor offsets. Synchronizer position learning is also represented. A failure in one of these records does not establish that every adaptation is absent.
The distinction between factory and online data matters after diagnosis: successfully completing one available learning operation does not necessarily validate an unrelated stored record. Equally, a code that appears immediately at controller initialization has a different timing context from a dynamic shift-performance complaint.
What to establish before relearning
Read any available adaptation-status details and retain the controller's initialization history, service history and companion faults. Determine which data category is reported invalid before deciding whether a specified learning routine is relevant. The source describes validation of records; it does not give a universal reset sequence or state that erasing all adaptations repairs the underlying issue.
Verification should include the applicable controller initialization and confirmation that the affected learning data is valid afterward. A brief drive without a warning is not equivalent to checking the stored-data decision. Programming, initialization and learning prerequisites must come from the exact transmission service procedure.
Source and applicability
2025 GM 07A-2 documented monitor only; module and calibration applicability must be matched to the vehicle. The application-matrix filename join remains unresolved; no model or engine fitment is inferred. GM PDF, page 1031.
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
Transmission Adaptive Values Not Learned
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