Élément de friction de boîte usé

A clutch pack or band inside the gearbox that has lost friction material and no longer grips as it should.

These are the parts a gear is actually made of. An automatic selects a ratio by applying two or three elements at once; each is a stack of steel and friction plates squeezed together hydraulically, or a band wrapped round a drum. Wear shows first as time, not as failure — the element takes longer to grab, which the module measures as apply time and reports before anything feels wrong.

Slipping is what wears them, and slipping is self-accelerating. A clutch that slips generates heat; heat degrades the fluid; degraded fluid carries less pressure and grips worse, so it slips more. The debris shed along the way circulates into solenoids and valve bodies that were healthy, which is how one worn element becomes a rebuilt transmission.

Do not assume wear from the code alone. Low pressure produces identical symptoms and identical apply-time codes, and it comes from fluid, seals, a pump or a solenoid — all of them cheaper than opening the gearbox. Pressure testing before disassembly is the step worth insisting on.

Which physical clutch a lettered element refers to is vehicle-specific; the standard does not say.