2000 Chevy Truck starter failure

Power will come from the battery, through a fuse box if equpped and to the starter. The secondary source will come from the ignition switch when you turn your key. The best way is to chase down the power loss from the two sources to find out where there is a loss at, most likely a fuse/relay or short in wires. May also be equiped with anti-theft shut off system. This too will have a relay.