Anyone know what they were bypassing?

Found a white plug under dash by clutch pedal that had a
loop of copper wire stuck into the neg/pos side of the white
harness.took the wire out and car wont start. Put it back in
and cranked up. Also when i plug the actual other half of
that white plastic harness into the other side it won't start.
Anyone have any idea what they bypassed so i can look
into getting it fixed correctly