OBD-II code · Powertrain (generic)

P0235 Turbocharger/Supercharger Boost Sensor "A" Circuit

The ECU detected an electrical fault in the primary (A) boost pressure sensor circuit. The signal does not match plausibility checks against MAP, RPM, and load. With no boost feedback, the ECU typically limits boost via the wastegate.

Is it safe to drive with P0235?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelyBoost pressure sensor failed
  • PossibleWiring or connector fault

Symptoms

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

Repair at a glance

Difficulty
Medium
DIY friendly
Often, with basic tools
Typical labour
0.3–2 h
Emissions test
Likely to fail
Parts involved
Boost Pressure Sensor, Boost Sensor Wiring, Turbocharger

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.