Diagnostic article Generic OBD-II
P283A: Rod-two intermittent feedback is monitored through its frequency
P283A checks whether the digital rod-two signal runs outside its frequency band rather than assuming every fault is a loose connection.
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Documented application
2025 GM 25OBDG07A Part 2 documented monitor only; its application-matrix filename join is unresolved. No model, engine or universal calibration applicability 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.
P283A is the rod-two position-signal frequency diagnostic in this GM implementation. The table rejects frequency below 1,500 Hz or above 2,500 Hz for at least 150 ms. That is a concrete timing criterion behind the generic intermittent-circuit description.
Pulse presence is not enough
A signal can contain pulses yet fail because they arrive too slowly or too quickly. Conversely, a changing mechanical position does not itself prove a frequency failure. The carrier timing and the converted position reading should be treated as separate diagnostic information.
VREF1 enable limits in the source are internally inconsistent: the table prints above 5.5 V and below 4.5 V. This article retains that limitation and does not invent a corrected interval. Supply-related inhibit codes are also listed.
Useful follow-up data
Preserve measured frequency, the duration of its excursion and reference-supply diagnostic state. A continuity check alone cannot verify this monitor, and a stable displayed fork position does not establish that the input frequency stayed valid. Resolve exact supply eligibility and the permitted signal-test method through the vehicle’s service information. The DTC does not identify a mechanically damaged fork or a specific defective connection by itself.
Document scope and source
2025 GM 25OBDG07A Part 2 documented monitor only; its application-matrix filename join is unresolved. No model, engine or universal calibration applicability is inferred. These figures explain the cited controller logic, not a vehicle-specific repair instruction. Match the vehicle’s service information before applying them.
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
Shift Fork B Position Circuit Intermittent
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