2001 Chevy S-10 Fuel pump

I have a 2001 Chevy S-10. I tested to see if it was the fuel pump by putting a small amount of gas to the carb and the truck starts. I then tetsed the fuses, the relay and the ground and it all checks out ok.
Thinking that it must be the fuel pump gone bad, I removed the pump to be sure and tested it against a 12 volt source and the pump does in fact work.
The pump isnt getting power from the source. What else could it be?