An LED lighting array system includes discrete lighting modules spatially arrayed along a support member to provide illumination of items within a display case. The modules have a low overall height that results in them being mounted in a low-profile configuration at various locations along the support member. The modules include a housing with opposed first and second sets of side apertures, a plurality of internal reflecting surfaces associated with the apertures, respectively, an external lens, a multi-sided light engine and a group of side-emitting LEDs. During operation, a first portion of light generated by the side-emitting LEDs is discharged through apertures and the lens into the cooler to illuminate contents therein, while a second portion of light generated by the side-emitting LEDs is redirected by the reflecting surface through said apertures and the lens into the cooler.