Diagnostic article Generic OBD-II
P2C13: Exhaust Hall sensor A reports a shift with no matching request
Understand P2C13’s unexpected event sequence and why correct final position does not necessarily clear the concern.
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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.
P2C13 evaluates exhaust profile-position sensor A, described as exhaust Hall sensor 1 in the source. The GM monitor detects feedback consistent with a profile-pin shift when the controller sent no shift command. The code therefore concerns a mismatch between an event and its request, rather than a simple absence of voltage.
Follow the entire Hall-state sequence
The documented sequence traverses extending, extended and retracted states. A final retracted value can look normal even though the earlier movement was not requested. Recording only the endpoint would miss the monitor’s central evidence.
The state-boundary numbers on the page are internal feedback values without clear physical units. They cannot be substituted for a universal travel measurement or sensor-voltage specification. The supported relationship is between recognized state transitions and command history.
Ensure the timing references support that interpretation
A running engine, supply above 11 V and diagnostic enablement are required. Relevant crankshaft and intake/exhaust cam-sensor faults must not be active, because the profile sequence is interpreted in the engine’s operating context.
Four failed readings among five produce the stated result. Retain the exhaust A-channel sequence and reference status together. The monitor does not independently distinguish unintended mechanical pin movement from misleading Hall feedback. A vehicle-specific procedure must resolve that question before the code is treated as proof of a defective sensor or mechanism.
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 910.
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 A Range/Performance 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