First thing - check fuses perhaps? have you or anyone else changed the stereo or added anything to the stereo at all? This can blow a fuse to the central locking if the battery has not been disconnected before undertaking electrical work on the car - believe me - I did it to my brother's car and he was seething!
AND - just because you might not have changed the stereo, it doesn't mean the person you got it from didn't remove a stereo they may have put in the car and replaced it with the original! This is defo where to start methinks.
if that's not it, open the cupholder - open the credit card holder grab hold of them both and give them a firm ish, sharp tug. after that, you will see 2 torx screws to remove the climate control unit - GENTLY pull it out and check if there is a connector loose behind there or if there is a loose wire or something?
That's all I got man - that is the sum total of all my knowledge in the world.
Last edited by Back2Alfa; 28-04-14 at 14:41.