Brighten Up Your Driving Experience With This Simple Upgrade Inside Your Fuse Box. Simply Install The Gm All Lights On Module To Allow Your High-Beams, Low-Beams And Fog Lamps To Simultaneously Illuminate The Road Ahead. Once Installed The Gm All Lights On Module Will Turn On The High-Beams, Low Beams And Fog Lamps When You Turn On Your High-Beams. When The High-Beams Are Not Turned On Your Low-Beams And Fog Lights Will Function Normally. Please Note The Gm All Lights On Module Has Been Modified So That The Ground Spade Is No Longer Required For Operation In Any Of The Models That This Product Fits. Therefore, The Ground Spade Has Been Removed From This Kit. Fitment Guide: 2003-2007 Classic 2500-3500 Silverado/Sierra Installation 1. Remove The Relays Labeled: Fog Lp, Hdlp-Low, Drl, Hdlp-Hi 2. Lay The Gm All Lights On Circuit Board In The Location Shown (See Product Images) 3. Reinstall The Four Relays Back Into Their Original Location.