2003 Ford Expedition

I have tail lights working.

I also have power out of terminal # 1 & 5 at the brake light switch plug.

Nothing out of terminal #2 when I depress brake pedal.

There is evidence of overheating at ONE of the bulb sockets but not on the wire's. I'm going to cut the 3 wires going to that socket and check the socket for continuity this morning.

Thanks

Thanks for the advice. I've run out of time and have had to resort taking the vehicle to a repair shop.

Certainly.

It appears that a wire was "cut" coming from the stop light switch that goes to the stop lights. How this happens I have no idea. I suspect that when I took the car to get an electronic trailer brake assist installed about 2 months ago has something to do with it. I can't comprehend how a wire would cut itself when neatly harnessed with other wires.
Before taking it to the auto shop I did notice a white wire that had been cut. I assumed that it had been joined with the electronic brake assist box. Now magically that same wire is no longer cut.
Chances are I had been driving around since the electronic brake assist was installed without brake lights.