OBD-II Code · Sensors
P0235
Turbocharger Boost Sensor Circuit
Severity
medium
Worth booking. It costs fuel, emissions or comfort until it is fixed.
Can you drive it
Only if running normally
A short trip to a shop may be reasonable if the light is steady and the car runs normally. Stop safely for a flashing light, severe shaking, overheating, loss of power, or another urgent warning. The code alone cannot confirm safety.
Indicative cost (USD)
$150–$400
Varies by vehicle, diagnosis, parts, and local labor. This is not a repair quote.
Boost pressure sensor circuit fault.
How a shop works this
Work from evidence to part, not the other way round. A code names a circuit or a symptom; it does not name the part that failed.
Note every code that is set, not just this one.
Codes that appear together usually narrow the cause faster than any one of them read alone.
Read the freeze frame — the conditions the fault was recorded under.
Cold or warm, idle or load, road speed and engine speed. A fault that only appears cold is a different fault from one that only appears under load, even with the same code on the scanner.
Confirm the fault is current rather than history.
Clear the code and see whether it returns under those same conditions. A code that does not come back may have been logged during a repair, a flat battery, or a bad connection that has since been disturbed.
Then work the likely-causes list in the order shown.
That order is what a shop checks first for this code — wiring and connections before the component they run to, because a connector costs nothing to inspect and is a common answer.
If the code comes back after a repair, the underlying fault is still there. That is the point to bring in a scanner with live data and freeze-frame, or a shop that has one.
Common symptoms
- Check engine light
- Reduced boost
Likely causes
- Failed boost sensorMost common
- Wiring
Read the full diagnostic procedureP0235 indicates a circuit fault in the turbocharger boost sensor A signal, meaning the ECM cannot validate the sensor's output, often because the sig…
P0235 indicates a circuit fault in the turbocharger boost sensor A signal, meaning the ECM cannot validate the sensor's output, often because the signal is missing entirely or stuck at an out-of-range value.
Cheapest first
- scan live data and verify the boost or manifold absolute pressure sensor is reading roughly 14.5 to 14.7 psi (atmospheric) at key-on-engine-off at sea level, dropping to 4 to 8 psi at idle vacuum, and rising to 20 to 35 psi under boost.
- A reading frozen at 0 psi or pinned at maximum indicates a circuit problem rather than a calibration drift.
- Disconnect the sensor and verify 5.0 volts on the reference pin, ground under 0.1 volts, and that the signal wire shows expected voltage when the sensor is unplugged (usually pulled high to 4.9 volts by the ECM).
- Inspect the sensor port on the intake manifold or charge pipe for oil contamination, which is common on turbo engines with PCV blow-by and which fouls the sensor diaphragm.
- Caveat: many platforms share the 5-volt reference between MAP, boost, and other sensors; a single shorted sensor can take down the whole reference bus and set P0235 plus several others.
Vehicle-specific patternsFord 6.0L and 6.4L Power Stroke (2003-2010) commonly sets P0235 from oil-fouled MAP/boost sensors, requiring sensor cleaning or replacement every 50,…
- 2003-2010Ford 6.0L and 6.4L Power Stroke commonly sets P0235 from oil-fouled MAP/boost sensors, requiring sensor cleaning or replacement every 50,000 miles in heavy-duty use. Cummins ISB 5.9L and 6.7L (2003-2018 Ram HD) sees P0235 from boost sensor connector corrosion and wiring chafe at the turbo.
- 2008-2017VW/Audi 2.0T TSI sets P0235 from a failed manifold pressure sensor, a $50 part.
- 2011-2019Chevy Cruze 1.4T LUV sees P0235 from intake manifold boost sensor failure as a known weak point.
Estimated repair$40 to $400.
Look up another code
P0235 — frequently asked
What does a P0235 code mean?
Boost pressure sensor circuit fault.
What causes a P0235 code?
Common causes: Failed boost sensor; Wiring.
What are the symptoms of a P0235 code?
Typical symptoms: Check engine light; Reduced boost.
Is it safe to drive with a P0235 code?
Only if running normally. A short trip to a shop may be reasonable if the light is steady and the car runs normally. Stop safely for a flashing light, severe shaking, overheating, loss of power, or another urgent warning. The code alone cannot confirm safety. Estimated repair: $150-$400.
How do I diagnose a P0235 code?
Work from evidence to part, not the other way round. A code names a circuit or a symptom; it does not name the part that failed. 1. Note every code that is set, not just this one. 2. Read the freeze frame — the conditions the fault was recorded under. 3. Confirm the fault is current rather than history. 4. Then work the likely-causes list in the order shown.
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