Diagnostic article Generic OBD-II
P2C19: Exhaust sensor B remains electrically high after switch-off
Learn why P2C19 requires off-state evidence and cannot be confirmed from profile position alone.
Read before applying this article
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.
P2C19 is the exhaust profile-position sensor B circuit-high result in the cited GM system. The controller evaluates the associated output after commanding it off and interprets the voltage through a short-to-power classification. The meaningful finding is electrical behavior inconsistent with the off request.
Distinguish residual power from an ordinary on command
The published controller limits represent impedance below 0.5 Ω toward controller power. They do not provide a universal voltage specification at an unidentified connector. Voltage observed while the output is intentionally energized answers a different question.
The neighboring P2C18 low-circuit monitor uses the on state. A complete verification record should retain which command was active for the exact fault subtype, rather than treating all high or low values as independent of control state.
Preserve repeated failure and scope
The source requires supply above 11 V, ignition in crank or run and diagnostic enablement. Four failed reports out of five samples produce the row’s result, with one-trip reporting separately specified.
Keep the exhaust system and sensor-B channel identity explicit; the two B labels in the generic description do not define a cylinder or connector location. A valid mechanical position at another time does not locate the unwanted power path. The monitor cannot choose between wiring, a connected component and the controller without the applicable vehicle circuit investigation.
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 915. 25OBDG03B, PDF page 916.
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 High 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