Exhaust emission warning light

This warning light has come on on my dash on my Skoda Octavia VRS (2006).

There is no problems with the car at all and still drives really well. I am about 20 feet from a VW garage but they said they could scan it but as the Skoda and VW software is slightly different they might not be able to find out the cause and it will cost me £60 odd quid!!!

Any ideas what it might be, I was told it might be a sensor but without scanning it I wouldn't know. I have two Skoda dealers but they are a good 30 mins drive to both of them (one in Brighton and another in Turners Hill).