vauxhall combo 05 1.3cdti

hi i have a problem with the centrall locking.i press the lock button and indicators flash but doors do not lock.I have replaced the battery in fob and tried to syc,turned ign on for 30 secs then tried to press lock button but no joy.
Could it be a blown fuse or faulty relay.I have looked in the book but there is no listing for the centrall locking fuse or relay.Any help with this would be great thanks peter

if the lights are flashing it must be responding to the remote but you could try listening inside the car while operating for any relay clicks. have you tried the correct programming sequence?

the programming sequence is:
turn on ignition
programming mode is activated for 30 seconds only
depress lock or unlock button
central locking system operates to confirm operation