Good morning, hopefully there is someone out there to answer my question.

My '03 1.9tdi Avant had the reversing lights stuck on yesterday. First thought was a faulty switch but on closer inpection I've found that the wire leading to it, that goes over the gearbox, had worn through causing a short. Now my question is where does this wire lead to? Looking front on at the engine, the wire leads from the switch on the leaft of the gearbox, over the top then into a much larger group of wires and dissapears off to the right betwen the back of the engine and the bulkhead. There is little to no access to the wiring as the gap is only an inch or so. I was hoping to find the other ond of the wire, disconnect it and order a new wire to plug back in only there is no mention of the switch wiring anywhere that I can find.
Any assistance would be really appreciated.

Ben