P286AShift Fork E Unrequested Movement
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P286A flags fork E creeping out of the position that belongs to its current gear, although no shift was requested and no force is being applied. GM uses the code in the 2023 Corvette dual-clutch TCM as the Type A drift fault of rod 5: as long as even clutch speed and output speed confirm the gear the module believes is engaged, the measured rod position must stay inside wide tolerance limits around that gear, and leaving them for a confirmation time sets P286A. The test is blocked if the rod 5 sensor already has an electrical or consistency fault. GM also lists P286A among the triggers of a synchronizer recovery routine. A drifting fork can let a gear partly disengage under load; worn detents, leaking actuation valves and lost references are typical.
- What you may notice
- Gear on fork E jumps out or shudders under load
- Unexpected reshift or brief loss of drive
- Warning lamp and stored transmission code
- Likely causes
- PossibleWeak detent spring or worn detent notch on the fork E rod
- PossibleLeaking synchronizer actuation valve pushing the rod
- RarePosition reference of rod 5 lost after repair
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €3,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.