Central locking lost sync with key!!

[Louis_boostbus]

After pulling fuses one by one to see if any was broke i have now lost central locking by the key. How can i resync it? I only have the one key also.  Its a 2005 touran 

[Volkswagen Owners Club]

You should be able to sync it by locking and unlocking several times, you may need the ignition on for this procedure