A0004640318 Mercedes-Benz W220 molla a spirale cavo airbag volante – Originale usato e testato

Descrizione

Riferimento originale A0004640318. Un originale usato, testato Mercedes-Benz W220 S-Class clock spring — the spiral cable maintaining unbroken electrical paths between the rotating steering wheel and the chassis wiring loom.

The clock spring (also called spiral cable, squib, or rotary coupler) is a flat ribbon conductor coiled inside a plastic housing, mounted between the steering column and steering wheel hub. As the steering wheel rotates, the ribbon winds and unwinds, maintaining continuous electrical connections for the driver airbag pyrotechnic circuit, the horn, and all steering wheel-mounted controls (cruise, audio, phone, paddle shifters). Because the driver airbag circuit passes through this unit, it is a safety-critical component.

Horn failure or intermittent horn operation; driver airbag or SRS fault light on the dashboard — the most urgent sign, pointing to a broken airbag circuit that may prevent deployment; steering wheel-mounted audio, phone, cruise and paddle-shift controls all becoming unresponsive; a clicking or grinding sensation when the wheel is turned to full lock; or apparent damage to the ribbon conductor itself.

Safety-critical. A qualified technician must perform the installation — the airbag pyrotechnic squib is wired through this unit, and incorrect fitting may prevent airbag deployment in the event of a collision. All SRS fault codes must be reset with diagnostic equipment after replacement. Confirm the OEM reference against your vehicle’s exact specification before ordering. 14-day return window on unmodified parts.