P02C6Cylinder 12 - Fuel Trim at Max Limit
- 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
- These codes belong to an individual-cylinder fuel correction: a diesel's cylinder balance control measures each cylinder's crankshaft acceleration and adjusts its injection quantity; on petrol engines a cylinder-selective mixture control does the same. CARB requires the system to report when such a correction has used up its range or one cylinder causes an imbalance. P02C6 means the correction for cylinder 12 is at its upper limit: the module keeps giving this cylinder more fuel and still cannot even it out – a sign that the cylinder receives too little fuel or builds too little pressure. Cylinder 12 only exists on engines with twelve or more cylinders. GM and Ford use other codes for this (P0263 ff, P219A ff); no manufacturer document describing this code with thresholds was found, so the description follows CARB and published patents.
- What you may notice
- Check engine light on
- Rough idle, vibration
- Lack of power, possibly misfire
- Likely causes
- LikelyInjector of cylinder 12 coked or partly clogged
- PossibleCompression loss in this cylinder (valve, rings, leak at injector or glow plug)
- PossibleInjector circuit high-resistance or connector
- PossiblePetrol: false air at this cylinder's intake (manifold gasket)
- RareInjector correction code missing or wrong after replacement
- 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: €100 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.