try pulling the 5amp fuse for the keep alive memory that is located under the dash. If that doesn't do it try unbolting both negative battery posts from the batteries and turn the headlight switch on for at least 10 minutes . . . bolt back up and try that.
Does your front windshield leak water in?? PCM might be acting goofy b/c it's still getting wet . . .
Try drying truck out inside a garage for a day or two then try the wipers.