WE(dealer) always fabricate a new section of harness from the rt side of the fuel tank & run it into the deck lid as many times the wiring where the hinge pivots is stretched & a quick repair won't hold long.
YOU need to get into the harness beside the fuel tank.

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MERCEDES Benz Master Guild Technician (6 TIMES)
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44 years foreign automotive repair
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190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
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