Certainly could be other problems but the most likely would be the flasher. Many cars in the past actually used two flashers. One for the turn signals and one for the hazard flashers. If it is a car which uses the bi-metallic element type; the turn signal flasher would wear out long before the hazard one because of much greater use. This analysis is probably not valid for newer cars which use an electronic means of controlling these functions. Hope this helps.
An old car guy.
An old car guy.