Have the above message showing up the dash on my grande punto when indicating left only. Checked all lights and seem to be fine... what is the problem?

Checked with the indicator on?

Sounds like a short to me, check there isn't any water in the light cluster.

What was the cause in the end? My right rear indicator isnt working but all other lights on the car are ok. I've tried 3 bulbs but none work.

Check the plug on the back of the light fitting clean pins and plug with contact cleaner