Help figuring out the Hatch light circuit???

Guys,
Here's another one of those darn simple items that isn't critical, but buggs the heck out of me.
Up to last week when the hatch was opened the light came on. Now if you open the hatch the light doesn't come on.
The hatch light DOES come on when a door is opened or the dimmer switch is turned on.
What possible item failed that would cause this? Since the light works in all other settings except for opening the hatch, where should I start the search?

I did do a search here and found a similar thread, but there was no posted fix or outcome.
Any help is greatly appreciated.
Thanks again,
Ken

Thanks Bullit.
I know I have aged tremendously since dumping my prized 93, so forgive me...but I must be blind. Where is the hatch switch? I am probably looking right at it, but for the life of me I don't see it. I figured a switch of some sorts might be a culprit, but I can't find one. BTW, it all worked fine last week, but I was leaving the hatch open while working on it, so the light burned for long periods of time. Still works when I open the drivers door.
Thanks for helping the old fart here.
Ken

Thanks guys.
I'll get on it first thing tomorrow morning. If you could see, or have seen before we started working on this car, the condition of the wiring, you would be surprised the car had not been engulfed in flames by now. A 8 year old kid must have needed a school science project or something. I kid you not, this whole thing is a catastrophy and fire waiting to happen. Bare wires and connectors everywhere. I have already had 2 smoking wire incidents during the past week...and NO fuses involved! I have just finished redoing the complete engine bay, now I'm starting to work on the interior...god help me. I already filled a complete kitchen garbage sack with wires from under the dash! Not stock wires mind you....crap from old alarms, auto door locks, etc. I'm not joking. You should have seen my wife's amazed face when I showed her all the wire I pulled out. It was so heavy the Glad 13 gal sack ripped through the bottom. Yeah, I have my hands full with this one.
Thanks for the help. The good news is I just installed my new Steeda Triax shifter!!!
Ken