When raining...Truck acts crazy 1999-F250

[Dayz]

Guys, help me out. When it rains outside, I get all sorts of weird things happening; ABS light, overdrive light, radio on and Off, Fan working without key, door lights stays ON, relays are flickering all over the place. It is only when raining and/or after rain.

I cannot see where water would come in, but there must be something related. I have read about GEM Box...What is it, where can I find it and clean it possibly.

What can you guys recommend, it is mostly certainly caused by water, but where would be the junction of all the interior electrical.

If any of you has the wiring diagram, that would help me out.
Thanks
Erik

[NoRalPh]

There's a known problem with the windshield seal. Look up behind the fusebox for water to be dripping on your electronics there from a windshield leak...

[Big Angry Hillbilly]

Yup. Water in the GEM gets my vote, too.

Take the panel off under the steering column where the fuse box is. Pull that fuse box out and look in the back of it, betcha she's all full of water.

Windshield pillar seal leaks, if I recall correctly. Been a long time since I had to screw around with one of these.