If I'm not mistaken, there's already a relay in the engine compartment fusebox. I think it should be good as is, other than removing the connectors that hook to the stock lights and installing the PIAAs. I should have stated that I installed a winch bumper and could not reuse the stock fogs. I was unsure what wattage our stock harness could handle. I hope this info is useful to others who would like to have a simple soloution to using aftermarket fogs.