L322 2004 L322 Td6 RR Vogue - Developing problem with remote central door locking

When purchased, the doors all locked/unlocked ok with both the remote and the dashboard button. Without warning the N/S/R door lock ceased responding. The door can be opened from the inside. A couple of weeks ago, the N/S/F door lock became unreliable. Sometimes it will respond, other times, not. Occasionaly, the drivers door lock 'cycles' several times before completely unlocking. Here, the door card is begining to pull away from the rubber seal so may be mechanically interfering with the push button itself.

I have been through the RAVE Manual. As far as I can tell, the door locking actuator is inside the door latch mechanism. If the actuator motor/mechanism is mechanically faulty, can it be removed and stripped for repair, or is a new, complete, door latch mechanism required?

What I would like to do is test these door locking actuators electrically, but I can't figure out from the RAVE electrical diagrams, which connector and pins control the door locking actuators. Also, with the P bus, K bus and CAN bus, how are the actuators controlled? Are they simple controlled by +12V/0V or by a digital signal superimposed on the +12V power connectors?

Cheers

Gary

a case of pulling the card off the offending door and testing at the lock mech' plug. Before I bought mine (p38), the rear door had super locked and immobilized the whole car!!! I managed to jump the motor with a lawn mower battery! I have seen on here, locks being unreliable for this car, if I remember correctly...