A4 trouble starting
 

i have an issue with my A4 avanti. i put the key in ignition and she turns over
once and then fades and the flasher warning lights come on and do not go off
until you disconnect the battery. about a month ago i had to have new keys cut
due to losing the original one, and its been fine until now, just seems strange put key in , starts and then cuts off and flashers start flashing.it seems to me that some anti theft system is cutting in . so vehicle can not be used. i am now
stumped as anyone any ideas how to cure this i would be most grateful for any advice or even how to cure it, thank you:confused: