Remove/install PTC heater booster (R22) on chassis 454 with engine 639.939 — interior and engine bay locations.

Service procedure for PTC heater booster removal and installation on Smart Fortwo 454.

View full-size image ↗

See all HVAC & Comfort 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.