The wires always always always break inside the hinge flex area.
Rewire the power and ground using a hi-strand count flexible wire
and run it from behind the trunk bulkhead to the center of the trunk lid.
repairs made in the hinge area or close by will fail days later.
All will be fine afterwards.
Dr.D

__________________
Dr.Diesel -
Shop Foreman
Master Guild Mercedes-Benz Technician.

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