dome lite problem 300zx

When I open the door the dome lite does not go on but the floor lite's go on and off as
the door is open and closed.  When I move the switch on the dome lite it goes on but
when I move it to the door position, nothing.  Already replaced the bulb with an exact
replacement.  I was told to replace the room lamp relay???
When I looked in my maintenance manual it showed the control unit that the relay
plugs into in back of the drivers seat on the trunk side.  Took everything apart and
found only the fuel pump control unit with no relays plugged into it.  Nissan sent me a
new diagram showing the control unit under the drivers seat.  Took the drivers seat out,
nothing there????
Does anybody have any Idea's????,