central locking issues with my 96 A6 AVANT 2.5 TDI

1996 A6 AVANT 2.5 TDI (AEL) 103KW/EG2 M6S
This is my first audi,Which i have owned for about 1 month.I am currently having a few issues with the car,so expect a couple a threads from me concerning this.Firstly though the central locking,which all works ok of the key.But on the drivers side,the interior door handle no longer opens the door!,this would'nt be to much of a prob,exept when i take the car out of reverse it locks all the doors!!,so heres my next problem the central locking switch on the drivers door will only lock the car but not unlock it,so i have to open the window and unlock the car with the key to get out!!:zx11:
so can anyone please point me in the right direction as to what the problem is:confused:
Why does the car lock itself when i take it out of reverse??Why has the interior door handle stopped working??why does the interior central locking swith only work one way.Any help/advice would be greatly appreciated,
thanks dave

I'd suspect corroded connector contacts on the central locking vacuum pump. It's located under the back seat next to the battery encapsulated in a block of gray foam rubber. The foam occasionally gets wet and the water wicks straight to the connectors.

Pull the battery out to get to the pump. Remove and clean the connectors with electrical contact cleaner.

Good luck.