There are two standard ways of wiring up trailer lights here in North America, either combined turn signals with the brake lights or separate. Usually they are combined.

You have two options.

You can rewire the trailer with new lights, and match it to your vehicle. Not a great idea if all Australian vehicles use a different standard, but it would work.

You can check the pin out connections on the trailer wiring harness (in the right rear luggage area, it is a 12 pin connector) and use a test light to see if some of the pins not being used work for your lights. You would need a new socket on the tow bar, and to wire it back up to the 12 pin plug.

I suppose the third way would be to get the correct wiring harness.

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