sounds daft i had the same problem with my galaxy i bought a new switch ands they still didnt work when you open the back doors there is a thick rubber with wires in pull it back and make sure none of the wires are split if not go to the boot and on the drivers side at the top there is another thick rubber with wires in one of my wires weere cut i rejoined them and now working fine the coulor of the wire for the reversing lights is black and blue i hope this helps
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