Thanks guys for your prompt response. I've been trying to trace the faulty switch problem anyway. I pulled the lock out, and there is continuity between pins 1 (green, door switch?) and 2 (gnd) when the door is open, and open circuit when closed. Similarly there is continuity between pins 2 and 6 (pink) when door is locked, and pins 2 and 4 (beige) when unlocked. (I think I got that right way round, I'm second guessing now). 3 (beige) and 5 (orange) had 2-300 ohms between them, typical of a lock motor. So, looks like the lock works as advertised and the fault is not there.
I don't think this model has deadlocking, I couldn't make it work if it does. Might be an Australian Design Rules thing, given our national phobia of locking kids in hot cars.
Then I unlocked the connector in between the door and chassis (how does that white locking ring and rubber seal go back together BTW?). The third pin from one end on one row had both the pink and green wire from the lock connected to it, and the corresponding pin on the other row was connected to pin 4.
This is where I get a bit lost because I haven't found a wiring diagram for the BSI on a multiplexed 206 yet. A bit of trial and error, but I could not find where the other of those wires were on the BSI. Does anyone have such a diagram? It is the BSI with the big grey shunt fuse in the middle of it, and a green connector to the right.
For some reason, it had an aftermarket central locking unit put on, maybe previous owner wanted two keys with remote and thought that effort was preferable to paying Peugeot for another key. I'm starting to think it was done to solve other issues with the factory system. I have now pulled all of that off, I don't think anything was cut to install it. It had connection to the indicators, power and a separate actuator that was hooked up in tandem with the OEM door lock knob.
However, when I put it all back together, the drivers door is now in full manual mode. And yes, I did plug it back in.