i have a 1998 ford f150 we were replacing the lisense plate lights and when i cut the wiring to the one light i lost power to the fuse block what could it be ?
You lost all power to fuse box after cutting into a rear wiring harness for license light? You may have caused a temporary short to ground that blew the main fuse. Check all your fuses, but if they are okay then check the fusible links. (in the advent of a major short those are designed to blow). You can google what and where your fusible links are for your vehicle.