well the fans come on because something is getting hot, not because the fans are faulty.
You'll want to check your coolant levels, make sure there's no air blockages, check your rad condition, and perhaps also your thermostat. If this wasn't opening properly, the car would obviously get hotter.
When I had my FMIC fitted, I noticed my fans coming on more often, as well as a few overheating issues. (Rad not getting as much airflow, sat in hot weather in traffic) However, this was cured with a new thermostat, so mine might well have been failing.
I know some people have also fitted a Neuspeed Thermostat - this operates at a lower temp, so opens the airflow to the rad earlier, meaning less issues.
I don't think you've got an FMIC - so probably not the case here - but I'd definately check out the above.
Incidentally - If I leave my 306 idling for more than about 4 minutes, my fans kick in too. They switch off as soon as I start moving again, and I've not got any overheating issues.