OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Powertrain generic / SAE

P2542

Low Pressure Fuel System Sensor Circuit High

The low-pressure fuel system sensor signal voltage is above the upper limit. Either a short to reference voltage in the signal line, an open signal return, or a sensor reading pegged high after an internal failure. The HP-pump pressure-control strategy falls back to default.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number5 / 42

Possible causes

  • Signal wire shorted to reference voltage high
  • Open signal return medium
  • Connector pins corroded - high contact resistance low

Inspection / repair

  • Difficulty: medium
  • DIY: shop recommended
  • Estimated cost: 120–500 €
  • Estimated time: 0.5–2 h
  • Component: lp fuel pressure sensor
  • Component: sensor wiring
  • MIL / check engine light
  • emissions-relevant

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication