Engine 132.9 coolant circulation diagram for model 451.3/4 showing thermostat, pump, radiator, and heating circuit routing.

Coolant flow schematic with labeled components: engine, thermostat, pump, radiator, heater exchanger, and expansion reservoir.

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See all Powertrain 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.