How can i fix my central locking fiat punto mk1?

Hi all, been trying to sort this problem for a few years now and have still had no luck... basically my passenger door wasnt connected to the rest of the car central locking.... so i have plugged in the plug that was hanging next to the socket.... and hey presto if i lock it from the passenger side all locks go down and the whole car locks.... but i try locking it from the drivers side and it puts drivers door and two rear door locks down and then they pop back up again where as the passsenger door pin doesnt move at all.... is there anything i can do? tinker some wiring or something??

Fiat Punto MK1 1998 R reg 5 door 16v 85 ELX

Ok so i have disconnected the master lock.... and then when i came to re attach it none of the central locking would work !! is there a fix?? i have attached the passenger door that was disconnected and now that works. its as if it has swapped sides from the left door not working and the rest of the locking working to the right door not working and the left door being the master !! HELP

Many Thanks

Dave