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

P2374

Turbocharger Inlet Pressure Sensor B Circuit

The pressure sensor at the inlet of the second turbocharger (B) - on twin-turbo or sequential-turbo systems - is reporting a circuit fault. The ECU cannot determine inlet pressure and falls back to a substitute value, which limits boost control accuracy on this stage.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number3 / 74

Possible causes

  • Open in sensor signal, supply or ground high
  • Connector corroded by underhood moisture medium

Symptoms

  • Check engine light on
  • Significant power loss / limp mode
  • Possible blue or black smoke from exhaust
  • Whistling or hissing sound from intake

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 120–400 €
  • Estimated time: 0.6–1.6 h
  • Component: turbo inlet pressure sensor b
  • Component: turbocharger b
  • 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