indicator fault

Hey guys heres one for the electrical minded, today whilst out in my 95 300tdi the right hand indicator started to flash fast as it there was a bulb off, so i stopped and checked it and all 3 bulbs on the o/s were working but flashing fast? The n/s works fine and so do the hazards.

Any ideas?

Strange but i'd replace the front and rear bulbs first the rears are a pain I know
Second the lamp units earth and thired the indicator relay.
But thats what i would do.

Usually caused by dodgy earth or oxidisation / corrosion of the bulb contacts or housing.
Sometimes merely taking bulbs out and refitting them can cure it as cleans the contact surface.