Door ajar problem

[Grayfox 54]

Yeah, I know, new guy, old problem. But this time with a twist.

My son purchased a 1999 Explorer XLT 2WD. The door ajar light and chime keep coming on while driving. I've done some research and found lots of info.
However, in all the cases and cures I've read the light and/or chime stay on all the time. In this car the problem is intermittent. Comes and goes with no decernable pattern.
Already tried the WD40 trick, I've checked and adjusted doors and latches as needed, checked the rear hatch and window, etc and so on. No luck.
The biggest problem I'm having is that it won't malfunction when I'm trying to find the problem. It only happens when the vehicle is moving.

I also noticed in my research that its often asked if the rear wiper is works. As a matter of fact, no it doesn't.

Could I be looking at a GEM problem?

This thing is driving me nuts. Any and all suggestions are welcome.

 

[koda2000]

the reason the rear wiper not working may be relevant, is because the wiper will not work if the rear glass is open (or the truck thinks it's open). then again, these rear wiper motors are rather notorious for not working.

 

[crunchie_frog]

My two cents. I would find out which door it is coming from first. My guess would be the rear hatch, you can disconnect these relatively easily (remove the panel and reach back in look in with a flashlight and disconnect. See if it comes on after that. If not, repeat with others.