Unknown plug on passenger side of E40D drain pan

[Ironweiner519]

Just bought 94 idi turbo with E40D trans. Shifted super hard when I first purchased. Checked FIPL and found it not sending correct voltage. Fixed that with not much of a change, a little smoother but still harder shifts than it should be. Checked vss and that was OL so replaced that with a verified good vss and still getting the hard shift. Was looking around on the passenger side of the trans drain pan and noticed a plug that was just hanging. Couldn’t find its home anywhere so figured I’d ask some of you more experienced guys for help. Appears to be a yellow&black wire and a solid red wire coming off the plug

 

[Black dawg]

I dont recognize that as ford wiring. Where does it come from?

Also, maybe I missed it, but did you get yhe tps adjusted to within the acceptable range?

 

[Ironweiner519]

Yes got that set to 1v currently. Still had erratic hard shifts so I looked into the VSS which ohmed out perfect and the magnet was strong. I then noticed the PSOM was never calibrated to the new 33” tires which I’ve read can cause shift issues. They only thing that confuses me is the trucks speedo and tach seem to operate fine and at the right speeds. But still going to recalibrate it once u get home.

As far as that connector goes I have no idea I didn’t have the time yesterday to trace it back. If I remember correctly it went into what appeared to be a factory wire harness. I will get more info here in about 2 hours