Found these mysterious wires in my Z

RonRizz

Except possibly your head units outputs, and your amplifiers inputs. If your rcas are questionable, get out your DMM and test continuity. If you replace an end on an rca cable, test continuity before putting into service. Bad means Bad for a reason.
Reading the prior posts, the OP's rca cables appeared to have been cut.
his choices are to repair or replace. there is no other option here.

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