Rear Number Plate Light Wiring

Long time lurker and Defender td5 90 owner here. Was just looking at how I might add an additional reverse light by wiring it to the existing reverse light wiring. When I removed the internal passenger side rear cover I discovered a pair of unused connectors bound with the number plate light/rear wiring. Any idea what they might have been for? Rear speakers possibly? There are fully functioning and connected rear speakers above and either side of the rear door.

So anything connected would com on with sidelamps? Could have gone to power socket in the rear or to switch for a low lamp in the back. Sort of thing night hunters would do for light to prepare gear.
It is not standard so good a guess as any I recon.

What is your actual question? Your title says number plate light. You then talk about a reverse light and speakers????

Just wire to existing rev light, I assume you are using led rev lights?

That looks like a newer vehicle, do the new ones not have the wiring for fog and reverse on both sides like the old ones, 300tdi and earlier do, not sure about td5 and newer. I did the opposite and swapped the reverse light for a second fog because I have roof light I use for reveres but it used to be quite common to double them up and have a fog and reveres on each side as the wiring is already there. If using LED the load draw on the circuit will not be an issue either. Pic off google, not mine.

Black/Yellow and Black/Orange - they're for rear speakers.

Behind the cover on the other side, you should also have Black/Blue and Black/Green.

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