door,tailgate ,locks

having a feww locking problems,ok quite a few.
If I arm it with the fob,yep it works the passenger door locks as do the rears,drivers and tailgate dont. If i lock it with the key,drivers door locks only,passenger,rear tailgate dont.
Can anyone explain in basic terms how the locking system works? Does the becm not send power to the locks when it in lock mode ? suppose it must do really as the button goes down but how does it work on the tailgate?
I played a bit today with it and opened the top and bottom tail gates then closed the lock arm on the middle latch and on the two lower lock locks so to speak,thinking I could fool it into thinking the top and bottom are both closed.tried locking it with the fob and the key but no joy both opened faultlessly. I cant see if theres an arm or a lug on the switch itself that should move to a llock position,told you I was ddim.
Any help appreciated
oh she's an 18 yr old young lady (love saying that,lol) ok ok
1996 dte diesel p38 right hand drive (uk)

I've had a look into this myself as my fob doesn't work at all nor does the central locking, unlock using the key only opens the driver's door and tailgate. If I lock/unlock via the button on the door then it only unlocks/lock that individual door.

From what I've found out, the becm controls the front passenger and rear doors (?) while the front outstation controls the drivers door and tailgate (there's a microswitch in the drivers door lock which supplies power to the tailgate lock).

I think there are two fuses but as it does work (although not as it should) I would say that they are getting power. It almost sounds as though it's out of sync.

I know this hasn't been terribly usefull but would be interested in what other people may suggest.

mick

P.S mines a 96 dse too, bet yours hasn't done as many miles though!

My drivers side had a mind of its own,locked when it it decided to on key fob and that coincided with boot lock,replaced drivers lock with new 1 from island4x4 and sorted both problems..passenger side next!

Drivers door lock motor failed by the sound of it. If you have an early RF receiver, that may well be the cause of the lock motor failing.