The hazard switch is the likely cause of your turn signal problem. There are lots (10 ?) wires on the back of the switch, and they can effect many electrical items. When you pull your switch out, mark each wire as to where it goes. To remove there is a ring on the back side. Loosen that, then push it forward a little, look behind and mark the wires, before you pull it out.
Try cleaning it with contact cleaner before you buy a replacement.
The part is, available new from the usual Pantera vendors for around $65 ???
Chuck
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