I never had a Fluval so this might just be a stab in the dark:
Try to figure out if it is electrical or mechanical -
Eliminate electrical by -
Trying a different outlet as An t-iasg suggested.
listening for humming or other signs of life.
checking the fuse in your filter, powerbar, GFI, house circuits.
Check for mechanical problems -
Disassemble everything, including the impeller assembly to make sure nothing is stuck in the impeller or blocking the water flow.
Any valves left closed? anything got sucked into your input or output hose? Disassemble all hoses & connectors to make sure free water path.
Remove all media/baskets (keep wet) - try running the filter empty - see if pump works.
Good luck!