Diagnostic article Generic OBD-II
P2541: low fuel-pressure sensor voltage is not a direct low-pressure measurement
Audi's CAED P2541 monitor uses sensor voltage below 0.21 V, requiring signal assessment before a low-pressure pump diagnosis.
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Documented application
Audi 2014 A6/S6 Quick Reference Specification Book, September 2013, Engine Code CAED, DTC chart. Thresholds only describe this documented monitor; not universal across other makes or engines.
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.
P2541 is a low circuit signal from the low-pressure fuel-system sensor. Audi's CAED chart uses sensor voltage below 0.21 V as the detection criterion. The two uses of low should not be confused: one describes the fuel-system side being monitored, and the other describes its electrical feedback.
Signal credibility comes before pressure interpretation
The row does not provide a voltage-to-pressure conversion. As diagnostic reasoning, a reading below this electrical boundary cannot simply be translated into a statement that the fuel pump produces no pressure. The circuit must be assessed using the correct sensor and wiring information.
Nor does the code alone demonstrate a restricted filter or an empty tank. Those are different physical findings and are not listed as established causes by this monitor row.
Use the exact engine criterion
Audi's book includes other engine calibrations, so the CAED threshold is explicitly scoped here. The quick-reference entry provides no connector pinout, fuel-line opening procedure or mandatory sensor replacement. A supported repair explains the low signal and uses the relevant professional fuel-system checks where needed. This distinction prevents a circuit-low fault from being treated as a complete hydraulic-pressure diagnosis based only on its generic title.
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
Low Pressure Fuel System Sensor Circuit Low
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