Central Locking problem
 

Hi everyone! I am here for the first time and my experience and knowledge are not so vast...
The situation is very similar to the previous post: the original factory alarm (car was purchased from a dealer, so I hope so...) + central locking from the original fobs (x2). Recently the battery was replaced , and after it the siren has operated and whatever I did including removal the battery ground cable - did not help. I've cut off the siren cable and disconnected the connector from the alarm box under the steering wheel.
Actually, I don't need an alarm, but ability to open all the doors using the central locking with remote control fobs is really essential.
I tried to teach the fobs as described in the Service Manual, but unfortunately with no success... On the 4th time I can hear a click, so, as far as I understand, the key fob is learned, but after pulling out the key from ignition, nothing happens ...
Is it possible to do anything? If not, what are my options? Is it possible to put a different mechanism of central locking without disassembling the car too much?
Thanks in advance for any answer!
Sincerely, Victor