The Cadillac CTS (or Catera Touring Sedan) is a mid-size luxury sports car designed, engineered, manufactured and marketed by General Motors. General Motors introduced the CTS in 2002 as a 4-door sports sedan. Some model years of the Cadillac CTS have keyless entry remote fob smart keys that are onboard programmable, meaning a person can program the keyless entry remote fob smart key with no special equipment other than the keyless entry remote fob smart key programming instructions. However, other model years of the Cadillac CTS are not onboard programmable and require special equipment in order to program the keyless entry remote fob smart key.