Head/thoraxbag units R12/20 and R12/21 location and sensor placement in B-pillars, chassis 451.

Diagram showing driver and front passenger head/thoraxbag squib location on smart fortwo with sensor callouts.

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See all Electrical figures for the Fortwo (450), or browse the full figure library. Part numbers and callouts are community-sourced and cross-referenced against the manuals — confirm with your VIN before ordering.