When I open them, I get no puddle or top lighting, and instrument panel doesn't show that doors are open either.
So, the question is how does that switch/sensor works, and where is it located
The switch is integrated into the lock mechanism.
If you remove the door card, near the lock there is an access hole. Clipped on the inside of the door near the access hole are two connectors. One has 5 wires, the other two.
Unplug the two way connector ( the wire colours are Black and Grey/Yellow on the left hand door ). You want the half of the connector that doesn't
go to the lock. The wire goes from the connector across the inner door skin. Get a small piece of wire - try a small straightened out paper clip - and carefully insert the two ends into the connector. Be careful, the terminals can be easily damaged. With the connector bridged out, the interior lights should come on plus puddle/footwell lights and the warning light on the dashboard should illuminate when the ignition key is turned to 'MAR'.
Remove the bridging wire and the dash warning light will go off and a few seconds later the interior lights will go off.
If everything happens as you'd expect, then you probably have a faulty switch in the lock mechanism. If the fault persists when you do the test, you have a wiring fault somewhere.
Let me know what happens and if it looks like a wiring fault I'll look into it a bit more for you.