The reversing light activation signal leaves switch I081, ignition-operated (INT/A) via a connection between ignition switch H001 and pin 48 connector C of under-facia junction unit B002. Power is supplied to short-circuit junction D097D - pin 1- via fuse F31 housed in the junction unit. The short-circuit junction supplies, in turn, reversing light switch I081 from pin 5.When reverse is engaged, switch I081 closes - across pin G and pin H - and sends a signal to short-circuit junction D097D, pin 7, that governs activation of the bulb housed in tail-light F031.A signal also comes from parking sensor control unit (see function E3090).