I have a 97 Chevy cheyenne 3500 6.5 diesel, was working fine. when i went to start, no power to glow plugs, electric pump or injector pump. any ideas? i already checked the fuses and relays as well as the connections.

 

Did you use a test light to check all the fuses?
Sounds like you lost power to some circuits. Check battery connections and fuse links to start. Trying to recall if a failed ignition switch will cut power to those circuits.