1997 Buick Lesabre

Welcome to the forum. Did you use a test lite at the turn fuse circuit? The circuit goes hot when you turn on the key. Even if the fuse is good, you still need to check or voltage. There is probably a multiwire connector under the dash, close to steering column, for circuits going to and from the steering column, we can check some of those circuits. Some people like to do testing, some don't. Let me know.

You need to get at the multiwire connector, under dash, close to steering column, for circuits going to and from the column. Purple wire carries turn signal voltage to the multifunction switch. At the same connector, dark green wire carries voltage for right hand turn signal at the rear. Yellow wire carrie voltage for the left side turn. All repair info says to disarm airbag, where applicable, when working under the dash.

When checking the fuse circuit, use chassis ground, the fuse itself, probably has a bare spot over each leg, that you can touch with the testlite, to see if you have voltage. That way you don't have to remove the fuse. Not sure how you checked circuit?