Does something tell you when the car needs a service ie a light or warning on the computer?

Mine has just done 15000 miles from it's last service 6 months ago but nothing is indicated, when you turn it on it flashes -270 then -5179 what do these figures mean as they don't seem to have changed since I've had it? Any help?

As far as I can recall those figures indicate the number of days to the next service and mileage to next service. You need to check the handbook for exactly what but I think a minus figure indicates overdue by that amount.