My 2000 Silverado decided not to start. Nothing works due to no elect power. Had battery tested and it is good.
All connections seem tight no lights work.....nothing.
Clean your battery cables ends on both sides of the battery then go to the battery cable junction block and clean them also.
Check your ignition fuse A 40 AMP fuse (IGN 40 AMP) and the ignition C fuse (ING 20 AMP) fuse in the under hood fuse block.
Check the Mega fuse 125 AMP also.
In the electrical circuit is a fusible link; if this is blown you won't have power to the truck. I listed a schematic below.
Try these suggestions and get back to me with your results.
Schematic supplied by Alldata information website.