P0236: Turbocharger/Supercharger Boost Sensor A Circuit Range/Performance. Meaning, possible symptoms and checks before repair.
Meaning, symptoms, causes and checks
Boost pressure sensor A’s input is implausible for the monitored conditions. Measurement bias, pressure-path or circuit faults are possible; the code alone does not prove turbocharger failure. Identify the letter and sensor location from engine-specific information.
Affected system: Powertrain
Symptoms
- Reduced power and slow acceleration; boost may be limited.
- Engine warning light; sometimes the issue is apparent only in diagnostic data.
Possible causes
- Biased sensor, obstructed pressure port or faulty electrical connections.
- Leaking/restricted charge-air path or inaccurate comparison-pressure information.
What to check
- Identify sensor A and read related MAP/BARO or supply codes; note whether faults occur at key-on or under load.
- With the engine stopped and pressures equalized, compare its reading with atmospheric pressure and relevant sensors using OEM criteria.
- Inspect the sensing port, connections and hoses; verify reference, ground and signal integrity before removing the turbocharger.
- If static readings agree, compare requested/actual pressure under safe conditions and leak-test the intake at the permitted pressure.
- After repair, clear codes and recheck sensor A and comparison pressures under the original recorded conditions, following the manufacturer’s procedure.
Also written as: P0236-00, P023600, PO236 (some scan tools add the fault-type byte, e.g. -00).