Interior courtesy lights on all the time.

I have a 98 Windstar and the problem is electrical. Icon on Dash indicates all door are ajar but doors are closed. Interior lights stay on including step light near sliding door. Something commom to all interlocks is my best guess. It would be unlikely that all of the interlock switches ( ie, sliding door, L & R door handles and lift gate sensors) to turn off the courtesy lights have failed. My Haynes schematic shows all the inputs go to (Generic Electrical Module but I don't know where it is located. Help : Any ideas?

First check to see if the inside light switch is not turned on. then spray some good lubricant inside the door latshes one at a time and open and close door several times until you isolate which switch is causing the problem. When you find the sticking switch, the lights will go out as normal. Good luck and let us know. You can search the forum for some good info on this.

They are more than likely all related. The car thinks that one door is ajar and so the interior lights are on.

It is more than likely one of the door ajar sensors.
The front sensors are the obvious pushbuttons found in every car since I can remember. The sliding doors have the switches at the back of the door on the frame of the vehicle. It is a push button also. (the door ajar has nothing to do with the spring loaded contacts contrary to popular belief). The rear sensors are inside the hatch door. These are most likely the problem.

Do a search. About 3 weeks ago there was a thread that expalined how to open it up and clean the contacts. In fact I posted a lot in that thread too and I know it has all the information you need.

Thanks Way2old and DRW1000. After I posted my question I did a search and found tons of stuff on that problem. The previous owner took out all of the inside lights instead of finding the problem. Well I got a can of wd-40 to spray the latches. I know the oil will attract and accumulate more dirt but I don't want to pull the liftgate apart just yet. I'll let you both know how it turns out. Again, thanks for your response and help.

Geeting into the liftgate and doing the cleaning there will only take an hour or two. It is easier than it seems.

Getting into the liftgate and doing the cleaning there will only take an hour or two. It is easier than it seems.

Dittos on the wd-40 on the liftgate latches. It worked. Problem was cleared in about 4 minutes. Thanks for all the help on this problem. When it re-occurs, I'll remove the sensors and clean them.