Hell I have this butt connector I just noticed and trying to figure out what it is connected to but I wanted to know what the grey plug is that it is going into.

 

Follow the grey wire..

 

I'm going to after work just curious what that connector is for

 

I'm not seeing a grey connector.. I see a Grey wire that was spliced in.

 

White (in the picture) wire > butt connector > green and yellow wire > connector

 

I call those butt splice's.. not connectors.. a connector has either male or female pins. either way ...How do we know what it's for ?

 

Unplug the gray connector and find out...

 

A little searching I found post #31 (might be the grey plug)

https://www.f150forum.com/f38/powerf...239274/index4/

And post #74.... (looks to be what it's for)

https://www.f150forum.com/f38/powerf...239274/index8/

I haven't done this mod or read the entire thread, hopefully it will point you in the right direction.