Sounds like you have a bad ground to that light. Reground the light by cleaning the thread holes and bolts that mount the light or by adding a new wire to the light housing and mounting the other end of the wire to the frame.
2014 Rubicon, Mopar 2" lift w/Fox shox, RE Geo brackets, Teraflex monster front track bar, 285-70-17 Duratracs on 17x8.5 Level 8 Punch wheels. RBZ and PRS+, Bestop High Rock rack, High Access front bumper, Soft doors and a Trektop pro, Smittybilt Gen2 comp winch, Cobra 75WX.
2015 Jeep Renegade Trailhawk