Hi BLOW, am new here, but recently went on trip to Oregon from Washington in a torrential downpour. Got to Salem, OR and everything went nuts, dash lights, warning icons, wipers, blower, etc. When I turned the key off, everything was still "hot". Fiddled with the key a few times and the stuff quit doing it, but could still hear relay chattering under dash. Took to Ford. Yep, LEAKING WINDSHIELD, right down the A post and right into the fuse block/gem. This is a 98 Expy. Ford says "yep, a well known problem with the 97 - 02 Ford Expy's and F-150 but they wont do anything about it". I got the thing home, put a hair dryer to the fuse block/gem module and as things dried out everything started working again. You CAN NOT reseal a windshield unless you want to just make a ugly looking one. I am having my windshield replaced by Safelite tomorrow, then I will tackle the fuse block/gem problems. Can't really work on them till it warms up here, we are in middle of winter and I don't have a garage.!!
I just had my windshield replace by Safelite at their shop. I asked the installer if there were any signs of water leaks. He said the problem wasn't the windshield in these trucks. Its the seam sealer running along the sides of the roof. He said they dry up and crack, allowing water to get behind the windshield and down the A pillar.