Problems with 93 ford taurus back turn signals

The back turn signals on my 93 ford taurus wont work but the front ones do. i checked the fuses and the bulbs and everything was good. the brake lights work and the head lights but no turn signals. same with the hazard lights. front ones work but no back ones. what should i try?

If you have hazards and turn signals on the front then obviously the flasher is okay. if you have brake lights on the rear then the circuit is good. The turn signals, brake, hazard lights use the same element in the rear. Therefore the problem has to lie in the combo switch.