M10 318i courtesy lights.

[gooner1]

Rear drivers side light hasn't worked since I got the car, so
decided to rectify that by changing the bulbs.
Turns out there wasn't one installed in the non working side.
Put new bulb in and lights came on.
Closed doors, locked car, both lights still on.
Tried turning them off using all positions of the switches.
No joy.

Pressed the little button on the front doors, lights go out.
Is this just a case of cleaning the door switches or something
else Don't understand how manually operating the door switches works, while closing the doors doesn't.

Passenger light works perfectly when the drivers side bulb is removed btw.

[Speedtouch]

Does indeed sound like you need to remove the door switch(es) and clean/re-adjust them, or replace if necessary.

They lead a hard life, and often wear out or get corroded.

[gooner1]

Will try both yours and Mikes suggestions, Maurice.
Thanks to both.

[gooner1]

Sorted. Was the light unit itself.
Pinched one from my battered old touring and job's a good ,un.