Forgot to make mention of the license plate light wires in addition to the high center third brake light inside the rear hatch glass.

Hope your repair lasts. Though them 245, 145, and earlier rear hatch / tail gate (I've read the back door on a RWD Volvo wagon named both) hinges outlast most automobiles!

Though like some older makes and models as well as newer, the rear hatch / lift gate / tail gate hinges are wholly within the passenger / cargo compartment; interior to the rear hatch / lift gate / tail gate seal. The hinges are an assembly that the rear hatch / lift gate / tail gate hinges wiring dress into, like a cable tray.

While a pivoting span that turns a partial radius with each opening and closing, them made in Finland Volvo 145 / 245 rear hatch / tail gate hinges wire harness did quite well for service before require replacement.

I'll go with fine braided conductor alloy, like I'd mentioned before, in UV resist insulation meant for such tight quarters and a hard pivot the conductor / insulation, and sheathing (if used), maybe shrink fit.

And watch the hinge pin as it pulls through the front (and rear) hinge material with vibrational wear. The 145, 245 hinges can break in unexpected ways with extremely worn hinges. Easy to see at a sideways glance.

The bottom edge of the rear half of the hinge will appear lower, and in an extreme wear case, appear to rest on the roof.
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