My car is a 2003 Oldsmobile allero. We have put in a new starter, alternator, pulley tensioner, and gone thru 2 batteries. The power is not getting from battery to alternator. They thought the connectors to my battery were bad when they attempted to change them they seen that who ever put in my sound system before I bought the car wired it thru everything and did not mount it properly so wires melted. I’ve been told I need a new cable harness? Does this sound right?