Diagnostic article Generic OBD-II
P2C16: Exhaust profile-position sensor B is checked for an energized open path
Understand P2C16’s channel-B circuit evidence before inferring a mechanical exhaust profile fault.
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Documented application
2025 GM 25OBDG03B documented monitor only. Vehicle, engine and calibration applicability must be confirmed from the matching service information; no model 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.
P2C16 concerns the exhaust profile-position sensor B circuit’s open classification. The GM row evaluates the associated driver while its output is powered on. That electrical-integrity test is distinct from checking whether an exhaust profile pin completed the expected movement.
Identify the correct B designation
This code uses B both in the camshaft designation and in the sensor-channel designation. The table describes the exhaust camshaft system and its B position channel. Those labels identify the function, but do not themselves provide a physical sensor position or cylinder number.
Voltage is compared with module-specific open-load limits corresponding to impedance above 200 kΩ toward controller ground. The adjacent P2C17 performance row instead watches the legitimacy of a Hall-state sequence. A missing drive path and an implausible movement report should not be collapsed into one diagnosis.
Verify the on-state result
The output must be commanded on, supply above 11 V, ignition in crank or run and the diagnostic enabled. Four failures out of five samples produce the stated result, while reporting is classified separately as one trip.
Useful evidence preserves channel B’s electrical status and command rather than relying only on a decoded position. The source does not establish where the open path lies or which component failed. The correct wiring and driver procedure must localize the interruption before a repair decision is made.
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 913. 25OBDG03B, PDF page 914.
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 Position Sensor B Circuit 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