Can't remember if I have asked this before. Driving along the doors randomly all lock. This has happened in the past and I did get locked out with the key in the car and had to break a window. Thought it had stopped happening but yesterday it did after 3 miles and I unlocked on the armrest button but this repeated six times. I noticed that all the doors locked themselves but twice the passenger door immediately unlocked itself. The others didn't. Scan today no codes in full scan except in 44 steering assist - 00566  27-10 - Implausible Signal (which I don't think is relevant).

So. Random central locking fault. No codes. Intermittent odd/out of step passenger door lock. Worth checking the wire boot but if OK, new passenger door lock?

Happened twice today in 5 miles and once with the passenger door exiting the pattern after first locking. Door jamb looms looked at. Ebay lock on the way.

What spec of Fabia?

04 Fabia 4 door hatch Comfort 1.4 16v BBZ, electric front windows only, No aircon.

It’s probably the drivers lock module but worth checking the door wiring harness. 

Thanks for your help. The actual lock and its micro switches or is it also dependant on the window motors onboard circuitry or even the lock/unlock switch on the armrest?

I don’t follow the question 

I'm still baffled by the complexity of VAG electrics and probably overcomplicating it. I didn't know if the driver door lock itself has other electrical links within the door or it and the armrest lock/unlock button link only and directly back to the CCM.

The window motor is the control unit for the door. Everything goes through that. 

Sorted. It was the usual microswitch, the one held on with a metal U clip, (not the ones inside the motor board). Just for a change the switch plunger had worn down, enough to give intermittent contact when the car chassis flexed relative to the door. Wrong new ebay lock delivered but was able to siamese the various good bits together to make a full fix.