Welcome to this forum! I've moved your thread into the stock 2002-2005 section. Unplug the switch, then check to see if the lights turned off. If so, then test the switch with a continuity tester. It should turn on & off when you press it, and not be constantly on. If the switch appears to work, then reinstall it, and test it in place. The switch might have an intermittent short or might be out of alignment.