Three-way catalytic converter with O2 sensor locations upstream and downstream TWC on smart exhaust system.

Rear view of smart car showing catalytic converter underneath with labeled O2 sensors G3/1 and G3/2.

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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.