Coolant system drain and fill procedure for Smart 454.0 with engines 122.9, 134.9, 135.9, showing radiator, expansion reservoir, and drain plugs.

Engine coolant drain and fill components including radiator, cooling system cap, expansion reservoir, and drain plugs with callout numbers 1-9.

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See all Powertrain figures for the Fortwo / Forfour (453), 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.