Is it dead now, or is it intermittent?
I am not "up" on the wiring of that model, but I seem to remember that along about that time they started putting power relays in the system. I think they are in the fuse panel.
I'm sure someone will jump in who knows for sure.
In the meantime, if it is working now, try this.
Find a quiet place to work, turn off the radio, air conditioner, anything that might make noise when you turn on the switch.
Listen carefully when you switch the key from off to on. If you head a click, that should be the power relay.
Find it.
Some of the newer cars have more than one identical relay for different things. Headlights, horn, main power, etc.
And they plug in.
If yours has that, you are set.
The next time it quits, swap the main power relay for one of the others.
If that fixes it, get a new relay.
Or buy a new relay and swap it when the truck quits.
Unless it tends to get you in dangerous situations, I would wait until it quits to try a new relay.
Otherwise you will be driving around for weeks wondering if you fixed it.
I'm going to do some more research, but Rockauto does not show the type relays I was talking about for your vehicle.
It does show a large auxiliary power relay that might be the cause, but its not interchangeable with others.
