They're separate.
Your new problem could either be a short, blown fuse, bad turn signal switch, dirty/rusted bulb holder(s).
Don't overlook the central ground point under the dash, behind the gauge panel on the console. Above the tach is a stud which has 6 or 8 separate ground wires attached to it. Unbolt the ground, wire brush all the connections clean and re-tighten. Loose or corroded wires here can cause some really weird electrical problems.
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