1989 mercury cougar blinkers out fuse is good what else could be wrong your help needed

the bulb could be blown! if not l would say the wiring!

Make sure the emergency flasher are not on the on position

possible switch, ,,look on the crack between the steering and column ,,if the switch are made of a white plastic,,most like ly you have a switch problem

check your flasher too,

Make sure the ground connections at the bulbs are clean and tight.Check bulbs for continuity.Replace turn signal flasher unit.Check for power at the flasher with signal lever on.If no power the open circuit is in the signal switch in the column.