Just bought a bora, engine management light is on now, after just driving home



should i be worried?..... i had a timing belt snap on me on a GT TDI, so im concerned, obviously everyone says if its a keeper get the belt done, but was wondering if its a quick fix? any one had these? P1296, P0012, P0340, the car starts and drives ok, bt when 1st turned over it seems like a secondary fan kicks in then after about 2mins, dissappears and the car sounds fine
any help would be appreciated, im thinking replacing the crank sensor 1st?