سایش بازوی شناور یا مسیر مقاومتی فرستنده

The fuel level sender worn at the point it spends most of its life. These are usually a float on an arm wiping a resistive track, and the track wears where the wiper rests — which is around the level the owner habitually keeps the tank at.

So the fault is localised rather than general, and that is its signature. The gauge reads correctly through most of its range and then jumps, sticks or drops out over one band. A tank that reads normally when full and erratically around a quarter is a worn track, not a failing gauge or a wiring fault.

A dropout is read by the module as an implausible value and stored as a range or performance code, so the code names the circuit while the fault is mechanical wear. Watch the reported level across a full refill rather than testing at one point; a bent arm from careless pump replacement gives a reading that is wrong everywhere instead, which distinguishes the two immediately.