Ford Wiring/Electrical :: Dome Light Not Working - Tested Almost All Components?

I can't find out why my dome light doesn't work. I threw a bulb at it first, and then a tester but found no voltage with the door open or the dome lights dimmer roller clicked over to "interior lights on". I do get a door chime with the door open, so seemingly the door switch is working. Fuses 4 and 14 are good. They seem to be the related fuses.

Here's what I've checked.

1.. Fuses are all good.
2.. Removed and tested the relay. It tested properly, closing the large contacts when voltage is applied across the two coil terminals.
3.. 12V is present at the large left contact in the relay plug.
4.. I applied voltage to the relay output pin (the large contact next to ^^) in the fuse panel and get the dome/cargo lights to illuminate, so I know the wiring from the relay to the lights is good.
5.. The two smaller relay pins upper and lower look to be the relay coil/turn on contacts. (The middle contact is not used) There is 12v on one of them and it seems the other should be grounded with a door open or when the dash roller is rolled past the detent. I'm not getting this grounding signal.
6.. I do get a warning chime if I open the door while headlights are on etc, so it looks like the door switches are working.

Just got back in from some more testing... Here's a breakdown of how the relay works:

- Relay socket we're looking at is the upper socket.
- High amp 12V power is on the left large vertical contact. The relay's function is to port this voltage to the middle large vertical contact. (the load contact)
- The middle vertical contact (load contact) goes to the dome light and cargo lights.
- The upper horizontal contact is one end of the relay throw coil. This one has 12V present when probed.
- The middle horizontal contact is not used. (actually it's an empty socket with no female terminal behind it.)
- The lower horizontal contact needs ground applied to it to get the throw coil to close the high amp contacts.

With the relay plugged in, I was able to sneak a thin probe to the lower horizontal contact and ground it. The relay activated and the lights came on. So, for some reason I'm not getting the grounding signal to the relay with the dome light rocker or the doors open even though I get the door chime.

Apparently there is something between the door switches and the dome light/roller switch and the relay? Is this the GEM module? If so, I don't see the reason for anything between the switches and the relay? It should be a pretty basic relay circuit?

Is this something (GEM?) programmable, or testable? I don't want to throw parts at it. Looking for a wiring diagram, a diagnostic flow chart or a pin out?