Central locking weird issue

[Killerko]

Hey everybody,
I got a bit strange issue.. a few weeks ago while driving my central locking started to play up out of nowhere.
Locking/unlocking while driving, it even when as far as the whole electronic malfunctioned and I could not even use blinkers anymore and all dash went dark. I had to stop and shut down the car and restart and it all came back online..

That was the first day this issue happened, the next day I could not even start the car because the battery could not crank the engine, I've tried to charge it overnight but no go the next day. I knew the battery is old, so I replaced it and the car started no problem, but the central locking issue is still present to this day and Its still lock/unlock occasionally, I also lost remote funcionality (which I can pair myself with the pp2000) but the whole central locking is acting up very strangly. For example I can only unlock the car from passenger side. If I try to unlock the driver side, the door will open, but central locking will not unlock the rest of the car. Funny enough I can lock the whole car from driver side, but not unlock
Locking/unlocking working ok from passender side and when I unlock driver side only and start driving the rest of the car will unlock in a minute on it's own lol

Anybody got any idea what to check or what could be at fault? I've never seen anything like that on 406.
Could this have anything to do with water getting somewhere?

[steve_earwig]

Hullo,
I remember my (admittedly full-mux) D9 playing dead once, stop & restart cleared it like yours. Dunno, could be related, maybe something's got wet over winter, or maybe just the driver's door lock switch has collapsed or the wiring is waiving about. It's a pain to get the panel off but I think I'd start there, rather than start by pulling the carpets up. Tbh I cant remember if that happens on semi-muxes (the memory fades )

[WillNZ]

I would suspect water in the driver's side footwell. Have had this issue in the majority of the 406's I have owned. Corrodes the plugs under the carpet and causes all sorts of issues with the electrics.