Ramp signals improve traffic flow by controlling the rate at which vehicles enter the highway. The signals alternate from red to green lights to ensure vehicles enter the expressway in a spaced and steady manner. They will be located at all northbound and southbound entrance ramps along the Palmetto Express corridor. Ramp signals operate based on real time traffic conditions, and depending on the marked signs on each ramp, allow one or two vehicles to merge onto the highway per every green light.

Ramp signals will be activated after the express lanes become opertional. Traffic managers at the SunGuide Transportation Management Center (TMC) will activate ramp signals during typical times of heavy highway use, such as weekday rush-hour periods. However, they may also activate the signals in the case of traffic incident or special event that may impact regular highway operations. Advanced warning signs flash to alert motorists when these signals are turned on.