Installation Installation of Radar Sensor © Before attaching the sensors onto the rear bumper, make sure the inner bumper surface is clean and smooth. Dented or scratched surface could degrade the radar performance. + Keep the bumper clean at all the time, especially the areas in front of the radar sensors. For example: avoid dirt,clay, snow, stickers(including transparent stickers}, or others items covering the radars, which could prevent the radars, which could prevent the radars from operating normally.