Help: Help please, where does this loose wire go? Stingray 4 HH bass.

I bought a used EB Stingray 4 HH today from the shop. When i opened the active circuit cover to check inside (i needed to check because i was buying a used bass), i saw that chrome colored wire loose and its tip was in one of the screw holes also shown in the picture.

Isnt it supposed to be connected somewhere or is it normal? Never had an active bass or a Stingray before so i am clueless, please help.