keys help please

[nugnah1]

ok, just changed the ignition lock and reader on my car 1996 A4 1.8T, the old key was 4 digit, the new key is 7 digits, what is the procedure for recoding the key/ immobiliser, as the car will not start, i have vag-com software but not sure where to begin. Any help would be great, cheers jason.

ps they are the old style keys.

[peteA3tdi]

7 digits are for 99 on and have to be done by audi as you can't get the SKC code anymore
http://www.ross-tech.com/vag-com/cars/key-matching.html

if your new key is still the old type ie non flip take the keys apart and swop the chips over its the black thing about the size of a bit of rice next to the blade

[nugnah1]

ok, originally tried swapping the chips but still the car wouldn't start, spoke to ross-tech direct who said the 4 & 7 digit codes are for the immobiliser anyway, but using vag-com now, module 17, no response from controller. Any ideas.

cheers jason

ps I know alot of this has been covered before but I'm on the brink of torching the car, my wife has had the car 2 weeks and has not used it yet.