P2C06: Intake Hall sensor A reports a profile shift that was never requested

P2C06 is the intake profile-position sensor A performance result in the cited GM system. The document calls this Hall sensor 1 and describes feedback indicating a profile-pin shift when no shift command was sent. A signal can be electrically present yet fail this command-to-movement consistency check.

The order of states matters

GM recognizes extending, fully extended and retracted feedback states. The failure sequence traverses those states without the corresponding actuator request. A normal-looking final retracted value does not erase the earlier uncommanded sequence.

The printed state boundaries are internal feedback numbers without a clear physical unit on the page. The article does not convert them into universal voltage or travel specifications. The diagnostic distinction is the relationship between the observed sequence and the absent command.

Validate the timing references

The engine must be running, system voltage above 11 V and the diagnostic enabled. Relevant crankshaft and intake/exhaust cam-sensor faults must not be active. Those reference signals matter because the controller is interpreting profile events in an engine-cycle context.

Four failed readings out of five produce the stated result. Retain command history, Hall-state transitions and reference-signal status together. P2C06 does not by itself establish whether the pin physically shifted unexpectedly or the feedback falsely represented movement. The correct service procedure must resolve that distinction before replacing a sensor or actuator.

Source and applicability

2025 GM 25OBDG03B documented monitor only. Vehicle, engine and calibration applicability must be confirmed from the matching service information; no model fitment is inferred. These criteria explain controller logic, not a complete repair procedure. 25OBDG03B, PDF page 898.