Key fob Programming


Hallo new to club. Got a 2007 Sirion 1.3 sx in metallic black which is for sale. 64000 miles runs like a dream. Anyone interested message me thru club. Reason for sale , just bought 2009 1.0 Sirion to teach my son to drive.Cheaper insurance etc. Anyway, when we bought new 1.0 all c/l worked fine on the fob. We had to replace the rear tailgate lock & now we have done that , car will central lock on key, but will not c/l on fob. Done all things as per forum, disconnected battery & then hold both buttons for 20/30 seconds, but nothing happening. As I said car c/l's on key no problem but have tried disconnecting battery on numerous occasions, but no go. Fob battery is new so no probs there. Any help from other owners appreciated. All wiring to new lock must be ok or tailgate would not c/l on key.
Cheers Rayb