Diagnostic article Generic OBD-II
P03F4: Exhaust profile-C performance depends on whether movement was requested
Understand the uncommanded pin-motion strategy associated with GM P03F4 and why feedback must be matched to the correct request.
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Documented application
2025 GM 03B documented monitor only. Vehicle, engine and controller calibration applicability must be established separately; no model fitment is inferred from the file.
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.
P03F4 is listed generically as exhaust profile-actuator C performance or stuck off on bank 1. The GM row for exhaust profile actuator 3 focuses on a pin that fires without a command. That narrower strategy cannot be reconstructed from the generic label alone.
The abnormal relationship is movement without a request
The controller recognizes extending, extended and retracted feedback regions. For this monitor, entering the extension region in the absence of a command supplies the failure evidence. Movement during an intended profile change is not the same event, even if the final position is identical.
The source requires a running engine, supply above 11 V and diagnostic enablement. It counts four incorrect positions within five cylinder events and lists one-trip reporting. A static reading after the event cannot reveal the missing-command relationship or the number of eligible observations.
Keep feedback interpretation within the source limits
The numerical region boundaries have no clearly identified physical units in the table. They are not presented here as pin displacement, signal voltage or duty cycle. The generic stuck-off wording also remains distinct from the cited uncommanded-motion strategy.
A useful capture aligns the request and feedback sequence for actuator 3 specifically. Further service checks must distinguish real unwanted movement from incorrect feedback. The monitor summary does not identify a replacement part, prove a mechanical jam or justify manually forcing the exhaust profile mechanism.
Source and applicability
2025 GM 03B documented monitor only. Vehicle, engine and controller calibration applicability must be established separately; no model fitment is inferred from the file. GM PDF, physical page 446.
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
B Camshaft Profile Actuator C Control Performance/Stuck Off Bank 1
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