Please help me identify mystery plug hidden next to RR locker wire harness?

So yesterday I pulled out my front dash panel doing some electrical mods when I noticed an extra plug with nothing plugged into it all taped up just hanging there. I stopped for a moment and time froze (I believe part of it is that I still have some mental issues from just having a new kid 6 months ago... so I think it was like 10 min of confusion ) wondering if I forgot to plug something back in the last time I took the dash out to do some work. Well the mystery plug is just hanging there next to the set of wires that go to my factory rear diff locker toggle switch, ETC toggle switch and dimmer knob, wtf? Anyone know what this is supposed to plug into? I came up short on my thread search...if you know or have a linky, please share so I don't go insane!

Ideas that came up in my head:
-Is it for that toyota security window sensor thingamagiggy that I see in other rigs? (I do have a set of factory keyless remotes)
-Front diff factory locker switch that Toyota never executed and/or disclosed? (lol I wish it were)
-Passenger eject switch from Toyota R&D but decided not to execute due to safety reasons? (lol I wish it were x2)

My brain hurts... so tell me, WTH is it!??! Ahhhhh the suspense is killin me!

The mystery wire harness has 4 wires (see last pic below), 2 of them are white with black stripe, the other two are yellow. The plug housing is black and is female and is shaped similar to the cig lighter plugs we have in our 1st gens.

 

It's been a while since I had my dash apart, but I think that plug is for the optional glass sensor/led that is an option on our trucks. If you have keyless entry as standard you can add the optional toyota glass break sensor and led, and it plugs into an open harness under the dash. Is the plug/wire in question taped over itself? If it is, and it is long enough to cross over to the right of the steering wheel, its probably the plug for the glass sensor.

 

Thanks for the reply, very interesting! The mystery plug just hangs over the the thick spine of wires that lead to the other switches using factory black tape. I have seen some of our trucks where the glass sensor/led unit is installed in the same slot where the rear diff switch would be for those that don't have lockers so I wonder if the plug is purposely positioned there for a reason.

Here is one where the rig doesn't have a rear locker switch but glass sensor/led was installed:


I'll have to dig in to see if the plug actually extends to the right side of the steering column. I did notice while skimming the internets that there are actually two types of glass sensor/led units

One is a horizontal style that is installed at the very bottom center panel where you have the two blanks:




The other is a vertical style that is installed where the hazard normally is and the hazard relocated to the bottom panel:



Here's a shot of it where the hazard normally is:



I'm also reading a pretty nice writeup on customtacos here that talks more into the glass sensor/LED unit and possibly unlocking alarm features to my taco, that is...if I actually have one.

Thanks for the help!

 

I just found that mystery plug yesterday and I thought it might be for Manual Tacomas which come with a "Clutch Start Cancel" switch that goes in that area.