P03C0Cylinder 5 Pressure Sensor Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- Some diesels have a combustion pressure sensor in the glow plug; the engine module uses it to control injection for each cylinder. This code concerns cylinder 5. P03C0 means the sensor signal stays above its upper limit – typically an unplugged connector, an open signal or ground wire, or a short to positive. The only manufacturer we found using this code family, GM's European 2.0 CDTI four-cylinder diesel (Saab 9-5, 2010), uses it for cylinders 1 to 4: signal above the threshold for more than 2 s with the engine running, check engine light after two trips, displayed pressure 10,000 kPa. For cylinder 5, which only engines with at least 5 cylinders have, no manufacturer document available to us uses the code; the description follows that logic and CARB. Without the signal, combustion control for this cylinder is switched off.
- What you may notice
- Check engine light on (often after two trips)
- Usually barely noticeable – combustion control for the cylinder is switched off
- Possibly rougher running, more noise or slightly higher consumption
- Likely causes
- LikelyConnector off or loose, signal wire open
- PossibleSensor ground wire open
- PossibleSensor in the glow plug faulty
- RareSignal or reference wire shorted to positive
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.