Thermostat operation diagram showing cold engine state (A) and warm engine state (B) with expanding material and valve plate positions.

Cross-section diagram of thermostat in closed and open positions, labeled with component numbers 2-9.

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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.