Remember: everything Springtrap says is made up.

You have been given a task of performing a maintenance on an old animationic. Fazbear Entertainment wanted to get him into working condition. You are alone with him, sitting in the Parts & Services, you plug him into maintenance computer and begin the diagnostics. Everything was a swift routine, you grabbed a screwdriver to open the chest cavity of the animationic, but suddenly he has sprung to life without any warning.