Q&A

 Master

The truck has a 30Amp fuse link supplying power to the fuel pump relay and the main relay, a 15 Amp fuse then protects the fuel pump circuit. The black /blue wire at the fuel pump relay supplies power out to the fuel pump once the fuel pump relay pull in winding has been grounded by the pink/black wire at the fuel pump relay.
The Computer grounds that wire when it sees that the enging is cranking or running (ie has to see cranking signal, engine revolution signal). Relay is in the engine compartment fuse box it is the relay nearest row of fuses 1995 1/2 onwards, earlier trucks relay is in engine compartment fuse box it is the relay just above the row of fuses, closest to the front of the truck.