Seat heater (SIH) wiring diagram for model 451 chassis showing electrical circuit connections and component layout.

Wiring diagram for seat heater system with relays, switches, and electrical connections labeled.

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See all HVAC & Comfort 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.