OK. I need some help. I have no interior lights coming on when you open the doors. Running boards extend when door opens but no interior lights. I checked fuse- still good. Lights work manually--come on when you push them. I checked the dimmer switch to see if it was in off position. Nope set mid range of control. So, where do I go from here. I seems there is another timer control or convenience control that tells the interior lights to come on and go off after a set time depending on door position(open or closed). I cannot find any such module. Anyone have any ideas where I should start to look?

 

I don't know the answer for a Navigator, but if my Mercury Marauder had this problem I'd suspect the Lighting Control Module (LCM). I'd try to bark up that tree if you can find it.