How can I fix my Accenta 6 alarm keypad?

I have an Accenta 6 alarm system and for some reason I can't set the alarm. When I key in the code and set the alarm, zones 1, 3 and 5 light up and the alarm makes a broken beep sound continuously and won't set. I have to omit these zones to actually set the alarm. This is no good though as I have 3 zones that aren't set. Is there a way I can reset the keypad? I've looked online for a user manual but I've no success, I've only found a manual for Accenta 8. Any help would be gratefully received.