In South Carolina, the basic rules state that a golf cart can be driven by a licensed driver on any secondary road marked 35 mph, or under during daylight hours only. Some roads are not marked with a number even though they are numbered roads, such as Folly Road on Folly Beach, and Palm Boulevard on the Isle of Palms. These type of roads may be crossed over but not driven down. Driving at night it is strictly prohibited and enforced.
Here is a link to the South Carolina Department of Motor Vehicles website explaining golf cart rules and regulations.