Truck will not come on, no lights no sounds. Battery , starter and alt fine. What would be the most likely cause of this?

 

Sounds like a wireing nightmare? I would check any ground wires then trace the hot wires. Checked all the fuses?

 

Check efi fuse, maybe even test the starter relay. see if you can pull a code on it. Test the circuit opening relay. If that doesn't function, the gas pump wont turn on giving the engine the gas it needs to start.

 

Main fuse. Other fuse and the other fuse