According to my hand book I should be able to dead lock the doors by either turning the key in the door and holding it in position for a few seconds or by pressing the lock button on the keyfob twice within 3 seconds. Neither seems to work.

I did have a problem with a duff battery when I got the car (one touch windows not working, messages coming up on the display about low coolant levels etc) Anyway I bought a new battery and everything now is fine apart from the dead lock feature (which has never worked) Is there something I can do to programme the locks?

TIA