Main fuse

The main fuse is an item added to Fallout 3 in the Broken Steel add-on.

Overview
The main fuse is a quest item added in Broken Steel. On the quest Who Dares Wins, you find a broken fuse box that activates the train to the left. A robot named Presidential Metro sentry bot is carrying it. It is required to fix the train. Should the robot survive the ghoul attack, he will eventually replace it himself.

Related quests

 * Who Dares Wins

Bugs

 * There is a bug where, when picked up, the character immediately drops it, then it falls through the world.
 * After using the train another fuse can be added to the sentry bot's corpse, this tends to repeat itself every time you go to use the train.
 * After clearing the area of all ghouls, the (optional) quest of containing the security breach does not trigger as complete, so the sentry bot with the fuse does not complete repairs. To fix either reload a save or just kill the sentry bot and do the repairs yourself.