I'll check into this for you. Are you refering to the patch cables that connect between cars, plus to the Locomotive [similar to the remote cab control patch cables between multi "lashed up" units]? They hang along side the air brake line hoses.
Or are you refering to the car's specific interior wiring?

Let me check around to see what I can find.

Scott "S.E.T."

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!