I have a 2000 navigator that has about 90,000 miles. I am currently experiencing the interior lights and running board lights staying on while the door is closed. I have removed the fuse so that the lights will go off and not run down the battery, when i remove the fuse the radio, rear windshield wipers and windows don't work.

Are you also getting a "Door Ajar" warning while driving?

No door ajar light or nothing like that.

I would still double-check all the door and hatch switches. Also make sure there's no light switches partially ON. I once had a rear courtesy lamp switch not fully closed, looking at it... it looked OFF.. darn gave me a lot of trouble before I found it.