A vehicle-in-motion warning apparatus having one or more warning device and a light source in a housing. The warning device may be an audible, visual, or objecting-sensing device, and is mounted behind a grill which is integrally formed with the housing face. The light source is mounted in front of the housing face and covered with a removeable transparent cover. The housing may be either formed to fit a vehicle recess or alternatively formed to fit into a trailer hitch receiver. The associated wiring harness is terminated with a standard connector which allows the apparatus to be plugged into the existing vehicle wiring harness without modification, or a pigtail for splicing into the wiring harness.