1997 GMC sierra

OK so, the other day my turn signals started flashing rapidly on the drivers side only. So i checked which bulb it was that was out. The drivers rear turn bulb was out so i replaced it and all of the other ones in the back (drivers and pass.). I tried the signals again and still the same rapid blinking only on the drivers side. I then replaced the front driv. side marker bulb cause ik noticed it was not working as well. Still same result. The blinker flasher is fine and so is the light fuse. Dono what else to check. The brake light works fine when the lights are on but wont blink wit the turn sig activated

 

mine does that once and a while. check your wires that go to the light. you might have a bad conection. i just turn the signal on then wiggle the wires that go to the light. it should blink normally