Passenger side door wont unlock!

[Ladiesman_317]

Hello guys, i have a problem with my 3 door 9n which has remote central locking. The past few weeks the central locking has decided to be a pain in the backside! Basically when I try to unlock the car, the drivers side door will open, however the passenger side will just stay deadlocked. No matter what you try pulling the handle from the inside or even pressing the central locking unlock button from the drivers side door, nothing works... This goes on for lets say the best part of a week, then if I randomly press the central locking button from inside, hey presto! it unlocks lol. I called up VW Martins who were reluctant to give me the part number at first, as they knew I wouldn't get it fixed by them.. anyway, after receiving the part number and searching for it on eBay (3B2 837 015 A), i find that the number given to me has a letter short on the end. Most of the listings end with another letter after the A, like L, G, F and so on... Can someone shed some light on this, regarding which part i require. I will be very grateful if someone could help me here. Thanks.