Powertrain, generic (extended)

P2542 Low Pressure Fuel System Sensor Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2542 means the low-pressure fuel sensor reports a voltage above its permitted range. Deutz is explicit: its MD1 controller stores P2542 when the supply pressure sensor signal rises beyond its normal voltage or is shorted toward the high side (SPN 94, FMI 3), and the EMR system describes P2542-00 as a battery short. P2542 also appears in the list Ford published for the BOSS 302S engine module of 2014. VW, by contrast, does not use P2542 in its 2014 books for the Passat, CC and Touareg and files a signal above 4.80 V as P2539. Besides a short to the 5 V reference or battery voltage, a broken sensor ground can lift the signal. A falsely high reading can mask a real lack of supply pressure, so the engine may lose power without an obvious reason. P2541 is the low-side counterpart, P2540 the plausibility fault, P2543 short dropouts.

Likely causes

Signal wire shorted to the 5 V reference or battery voltage
Sensor ground wire or pin interrupted
Failed low-pressure fuel sensor with high output

Symptoms

  • Check engine light
  • Reduced power or stalling if real pressure is low
  • Hard starting

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–350
Time0.5–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

low pressure fuel sensorsensor wiring

Related codes

P2539P2540P2541P2543P008A

References: serdia.deutz.com, serdia.deutz.com, performanceparts.ford.com, static.nhtsa.gov.