Replace the flasher relay.
It should'nt
One of the bulbs is burned out. Turn on the blinker and look at the front and back turn signals to find out which one.
multi function switch( turn signal, lites etc)
turn signal relay fuse
Look from the outside. Either the front or back bulb is burned out.
your rear bulb is blown - replace the bulb The turn signal blinks fast because the bulb is going out. That is also why the others dont blink.
turn signal relay is bad
flasher will not flash when circuit is open or shorted replace left front turn signal bulb
Buy a "highway" turn signal flasher
Check your bulbs and your flasher.
Probably needs a fuse.
This may very well be a problem with your ground connections at that turn signal.