Has anybody worked on the wiring to "fix" a problem? Those "fixes" frequently involve finding some wire with voltage and tapping into that. The turn signals are powered through the ignition relay. If the key is not in ON, the ignition relay won't complete the circuit for the turn signals, As @Zed Head suggested, the next thing to look at would be the hazard lights. Normally if you pull the hazard switch that would kill the power to the turn signals. If the blinker is still going with the hazard switch disconnected, that would indicate some creative wiring has been done to the car. You can also pull the turn signal fuse to see if that kills the problem. If not, pull the hazard light fuse. The turn signal fuse is in blue, and the hazard light fuse is in red below. If neither fuse fixes the problem, that still points to creative wiring. More questions: How long have you owned the car? Have you experienced any other electrical glitches? Look under the dash on both sides and around the kick panels. Do any wires look like they have been spliced, cut, or otherwise altered? If so, look for wire colors (with stripes). Do you see any electrical tape that looks newer than the wiring harness?