1997 Cadillac STS TURNING SIGNAL

If it is affecting all four, I would suggest a flasher be replaced. It is located near the steering column under the dash. You can remove the lower left insulator, the knee bolster just pulls away, and there is a metal plate held with (4) 7mm or 10mm bolts. This should give you plenty of visual access. Try the hazard flashers, the sound of that flasher may lead you to the signal flasher. They are in the same general area.

i had this problem the device that holds the bulbs is burnt or has a short you need to find the one that is causing the problem and replace it find one at junk yard cheaper must be a defect with sts

In 93 thru 97, there were socket problems, particularly the ground of the socket. It would cause dim lights, erratic flashing and such. It would not cause complete turn signal failure unless it blew fuses due to bulb contacts that melted and shorted. This was a concern with Eldo, SLS, and STS as well.