P2871: Clutch A Performance/Stuck Disengaged
What to do
Expect missing or refused gears rather than total failure — the box is declining to use gears it cannot confirm. Driving on briefly is usually safe in the gears it still offers, but have it diagnosed soon: what starts as a sensor reading can also be the first sign of a fork or synchroniser wearing, and those get more expensive with every hard shift.
What this code means
Clutch A is not engaging — stuck disengaged.
Stuck disengaged means this clutch will not take torque, and half the gearbox goes with it. In a dual-clutch box, one clutch serves the odd gears and the other the even — a clutch that cannot engage removes its whole set. The box limps on the surviving clutch, so the car still moves but shifts feel wrong: gears arrive doubled, spacing is strange, and pulling away may use a gear it normally would not.
The cause is usually the apply side, not the plates. A clutch cannot engage without pressure behind its piston, so a failed actuator, a collapsed seal or a blocked feed is the ordinary story. Plates worn to nothing engage badly for a long, noisy time before they stop engaging at all — and that history is usually already in the adaptation codes.
Likely causes
Start here
- Faulty clutch actuator · specialist
- Low hydraulic pressure in the clutch actuator · specialist
Less common
- Leaking actuator seal · specialist
- Worn clutch packs · specialist
Symptoms
Components involved
Information, not instruction
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Community experience
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