Diagnostic article Generic OBD-II
P283E: Rod-three high is a waveform-quality fault on the VREF2 group
P283E evaluates static-high or excessive-duty behavior, and its continuation identifies the relevant reference-supply inhibits.
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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.
P283E is the electrical-high monitor for rod-three position. It checks for missing pulses while the pin exceeds 3.5 V, or duty cycle above 92%, with at least 150 ms confirmation. The high designation describes the digital input, not a high mechanical fork position.
The continuation identifies the supply group
The row begins on page 913 and its inhibit list continues on page 914. P0652/P0653 identify the VREF2-related supply context, alongside controller-voltage faults P0882/P0883. Reading only the first page would miss that distinction.
The printed VREF2 enable limits conflict, requiring above 5.5 V and below 4.5 V. This article keeps those limits unresolved rather than inventing a corrected range.
Different waveform failures need different evidence
A pulse-free high level and a still-pulsing signal with excessive duty are distinct paths to the same code. Preserve pulse activity, duty cycle and supply status together. A converted position reading or a single high-voltage sample cannot show which route failed. Confirm the vehicle calibration and service test method before evaluating the input. The summary does not isolate the sensor or another circuit component as the proven repair.
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 C Position Circuit High
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