آسیب سیم‌کشی در ستون فرمان

Damage to the looms inside or around the steering column — distinct from the clockspring, though the two are often confused and sometimes both are involved.

The column is unusually crowded for its size. Stalk switches, the horn, wheel controls, the steering angle sensor, the ignition switch or start button, the column lock and the airbag circuit all pass through or terminate there. So damage in one place takes several unrelated things with it, and a group of column-area failures is normally one loom rather than several parts.

Three mechanisms account for most of it. Adjustment: a column that rakes and reaches moves its wiring every time somebody changes position, and a loom routed slightly wrong after previous work chafes against the mechanism. Prior repair: airbags, clocksprings, columns, wheels and ignition switches are all removed for other jobs, and a loom pinched as the shrouds go back on is an ordinary outcome. And theft or attempted theft, which characteristically damages exactly this area.

The distinguishing test against a clockspring is free and worth knowing. A clockspring fault changes with steering wheel position, because the ribbon flexes as the wheel turns. Column wiring damage more often changes with column adjustment, or with vibration, or not at all.

One caution: the airbag circuit runs here. Its wiring is deliberately distinctive — commonly yellow, with shorting connectors — because it operates a pyrotechnic device, and it is not something to probe or repair casually.