If you let one door(no matter which one) open and lock with fob do you hear the misslock audible warning(short horn sound)? If not it means that the warning is disabled and one of the door switches is stuck closed so for the BCU a door is permanently open and it doesnt activate the courtesy lights... if you get misslock warning means that there's a problem on the earth path from the BCU to the lamps somewhere else than the header i pointed and to find it you must know how to troubleshoot that based on the diagram... unless it's a BCU faultchecked out both of these sugestions but still not working on opening the door but the light works if I switch on manualy ??