P283FShift Fork C Position Circuit Intermittent
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P283F stands for an unstable fork C position signal rather than a hard short or open. The rod 3 sensor in GM's Corvette dual-clutch gearbox runs at a carrier between 1500 and 2500 Hz; if the measured period puts it outside that band for 150 ms, the module records a Type A fault, as long as reference B and battery voltage are valid. Ford's TR9070 summary assigns the frequency check of rod sensor 3 to this code. Mercedes-Benz does not list it for the 8G-DCT, and Ford's DPS6 has no fork C at all. Because the signal survives most of the time, the cause is usually mechanical stress on the wiring: a connector that moves with engine rocking, corrosion on a terminal or a cracked insulation near hot parts. Shifts may falter only now and then.
- What you may notice
- Occasional stutter or delay on even-gear shifts
- Warning lamp appears only now and then
- Likely causes
- LikelyFork C connector working loose under engine movement
- PossibleCorroded terminal causing signal dropouts
- RareCracked insulation near hot components letting noise in
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.