Sounds like a burned out bulb to me!! Check both front a back on that side, and check the ground between the socket and housing as well. This usually is the cause of a non-flashing signal. The flasher is working if one side works!! Good luck, Geof
check the bulbs, if the flasher works on one side then it works properly. Power flows through the flasher in route to the turn signal switch the flasher doesn't care where the turn signal switch sends the current.