Hey, my friend has a 1999 Ford F-250 super duty, 5.4 v8 motor with about 148k miles, I do work for him on it since he's not to good with the stuff, I recently installed a 52" light bar on it and wires it up correctly and everything was fine, later on it would stay on constantly and flicker so we just unplugged it for now, the other day a relay thing went out and it's on the passenger side by the battery, we replaced that and everything's fine except when the truck is off and key is out you can turn the heat on and the heat works its weird and yesterday he was driving and the horn went off for now reason, the horn would shut off when the doors were open but when you close the door and the lights turn off the horn went off so I took out the fuse for now but we gotta fix it all and get it working properly, any ideas on what it could be or how I should check to see what's wrong first??? Any help would be greatly appreciated