P0235 — Turbocharger/Supercharger Boost Sensor A Circuit

P0235: Turbocharger/Supercharger Boost Sensor A Circuit — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

Turbocharger/Supercharger Boost Sensor A Circuit. Basic catalogue definition; diagnostic details have not yet been reviewed.

Affected system: Powertrain

Symptoms

  • Check-engine warning and possible reduced boost or acceleration.
  • The boost sensor A circuit has a detected fault, which must be distinguished from an actual boost-system problem.

Possible causes

  • Sensor A power, ground or signal wiring/connector fault.
  • Faulty sensor; boost leakage or actuator problems need separate mechanical confirmation.

What to check

  • Confirm P0235 and note any pressure-regulation or barometric-sensor faults.
  • Locate boost sensor A and inspect connector, harness and pressure port for damage/contamination.
  • With ignition on and engine off, compare indicated pressure with ambient pressure as appropriate for the sensor setup.
  • Test reference, ground and signal against OEM circuit specifications; assess the signal fault before substituting turbo components.
  • Repair the proven sensor/circuit issue and validate live boost readings under a controlled drive test.

Also written as: P0235-00, P023500, PO235 (some scan tools add the fault-type byte, e.g. -00).