I have a 1997 F150XLT Supercab that had one its turn signal modules replaced three years ago by an auto mechanic known to our family for years. When he did so, the truck became sensitive to rain. After a good rain the electric windows and wipers would not work till it dried out a few days! However, now it won't start till I have fooled with the steering column a bit, but tonight it died altogether at the grocery store. It wouldn't start, even after messing with turning the steering wheel left to right while charging the battery, as was successful before. So, I called my wife and we tried again to jump the battery, but a few minutes into the charge the theft alarm went off all by itself and would not stop, even by putting in the key and turning the system on. With that, I had to disconnect one pole of the battery to get it to stop and we towed it home without power. . .

 

drop the colum down, and look at the switch on top, as you turn the key on. My guess, the switch has come loose, and the rod is just pushing the switch back and forth

Put the key switch to off, tighten it down, then try it.

you may have to do some "fine tuning" to get it where it belongs

Tilt colums tend to loosen the switch when you use them

 

For the "rain" problem, I would look into water getting into the cab, and running down into the fuse panel

Have someone use a hose outside, while you lie on the floor with a flashlight, and watch for where it comes in, then take whatever steps you need to fix it

This is old body style wrrite ups, but you probably can use them on your truck
https://www.fordtruckzone.com/threads/cleaning-the-cowl-drains-on-a-80-96-f-series.657657/

https://www.fordtruckzone.com/threads/re-sealing-the-cowl-on-a-80-96-f-series.657653/

 

Check for power at the connector that goes to the drivers door it remember it is a 19 year of Vehical and things do come loose at times. I have an 03 winstar that the drivers window stops working when it is really dry. When it rains it start working.

 

Fuse panel gem is your issue. .....
Know problem.