can any one help I have just bought a 2000 year a4 2.4 se it had a problem with the clocks not working (gone mental) so bought a set of working second hand ones and fitted them today and now the car starts then cuts out strait away there is a light on the dash on the left hand clock that is the shape of a car with a key in it ? does any one now what has gone wrong

Your immobiliser is kicking in. You need to recode the key to the car.

i thought this bt when i fitted the old clocks back in the car started up and run fine so is there some thing i need to do to the car to take new clocks?

put the old clocks bk in, see if it works, if it does, get the ecu coded, there is key, barrel and dials, all need to say the same code, i just sent mine off to get the need for a cade removed from the ecu so i can put anything i want on my ecu now.

You need to plug in vcds and check what faults it has . 

My bet is Component Protection