Diagnostic article Generic OBD-II
P2542: A high electrical signal from the low-pressure fuel sensor
BMW P2542 is triggered by excessive low-pressure fuel-sensor voltage, not directly by measured fuel pressure.
Read before applying this article
Documented application
2011 BMW X6 xDrive50i (E71), N63 4.4L turbo; BMW DME monitor chart reproduced by Operation CHARM.
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.
BMW's 119201/P2542 monitor checks the upper voltage limit of the low-pressure fuel sensor. It recognizes a signal above 4.6 V and stores the entry if that condition lasts longer than half a second. The fault text identifies a short to positive.
Voltage and pressure are different evidence
The important quantity in this chart is sensor voltage. A scan tool may translate the sensor input into pressure, but an implausibly high electrical input can make that displayed pressure misleading. The code alone cannot establish that the fuel pump is actually producing excessive pressure.
The source identifies the wiring harness and the low-pressure sensor as potential causes. Its service direction checks the harness before replacing the sensor. That sequence favors verifying the integrity of the measurement path before making a pump or pressure-regulation decision.
What can be checked safely
A technician should use the correct wiring diagram and approved electrical tests to distinguish a circuit problem from the sensor itself. Fuel-system work requires the applicable depressurization and handling procedures; this short monitor chart does not provide them. There is no justification here for opening a fuel connection merely to see whether the indicated pressure seems high.
The entry is monitored with Terminal 15 and lists no specific apparent symptom or warning-lamp request. An absence of a lamp therefore does not invalidate a stored electrical fault in this calibration.
Verification should show a credible sensor signal without recurrence of the upper-voltage violation. A mechanical pressure assessment, if needed, is a separate controlled diagnostic step rather than a conclusion supplied by P2542.
Source and applicability
BMW diagnostic chart, P2542. 2011 BMW X6 xDrive50i (E71), N63 4.4L turbo; BMW DME monitor chart reproduced by Operation CHARM. These values describe that documented monitor; they are not universal specifications for every vehicle displaying this code.
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 High
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