there's a fun fun topic. The turnsignals work with a sequencer motor. The emergency flashers have a separate flasher unit that should do the front signals and the centers of the rear signals.
Sequencers are a topic on here somewhere. Try things like checking if the motor turns when you turn on your signals (you'd hear it clicking), the wires, etc. Should be a mounting board looking thing in your trunk, down inside the leftside.
When I got my car, the motor for the signals was burned out and someone had put a standard flasher unit on there to bypass the sequencer. I rebuilt the sequencer with a motor from a local electronics house and put a resistor inline to correct the speed.