Why won't the SweeperVac turn on?

The most common reason for this happening is a dead battery. The battery must either be charged or replaced.

If it is not the battery, the mechanism for turning on the device might be jammed. This mechanism is in the handle. To check this, try removing the handle entirely and examining the opening at the bottom while pressing the handle button. If it broken, there is little you can do, but is more likely to simply be stuck in which case pressing against the inner mechanism might free it up.