Smart fortwo 451 cooling system circuit diagram showing radiator, expansion reservoir, thermostat, coolant pump, and temperature sensor locations.

Cooling system schematic with numbered components: radiator, expansion reservoir, coolant pump, thermostat, and heater exchanger.

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See all Powertrain figures for the Fortwo (451), 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.