general idea is your DRL lights and the lights that flash when you use the remote operate by applying much less than full power to the bulbs. HIDs are not a fan of less than full power, so you have a choice. DRL Killer (also called DRL modifier) will disable the DRL completely, as well as the lights flashing with the remote, problem gone. DRL module will give full power to the lights whenever the truck tries to give half power, problem also gone. just a matter of preference which one you want to use. I went with DRL modifier from Jetttstream (look for him on here, he's a vendor) Mine keeps the auto on lights at night and also allowed me to hook up the quad high beams (lows stay on when i turn on the highs)i did not buy an drl killer what is that anyway?