Originally Posted by Aggiesrok
I've heard the smart junction box can cause weird stuff. They can wet and cause shorts. Also the frame can crack and cause trouble. It requires a scan tool to test it. Apparently they're expensive.
^+1 Check the passenger side carpet to see if it's soggy. Another way to check is pop the hood, remove the access panel to the cabin air filter (passenger side of the car) and look to see if it's filled with water. Ford designed the car with a double firewall. The 2 halves join together down near the footrest. To keep exhaust fumes out they use a "1 way" drains. Unfortunately, these fill with pine needles, seeds, leaves, etc and clog so water just starts filling up the void between the 2 firewalls. And to top that off, the cabin air filter just clips in about 3 inches above the drains, and it's a big square opening. So as water builds up, it just leaks into the car.