I guess it was my turn to have this part fail. I brought it to my dealer. He wanted $1,100 to replace the defective module ($ 700 part) and also wants 5 hours of labor. I took the part out in 20 minutes. Next, I sent it out to a guy who advertises on eBay for repairing this very common problem. Cost...$ 75.00, AND A GUARENTEE of never to fail again.
It seems that the Panther chasis for 03-04-05 used a control module with a defective thermal switch. When the car gets 50k miles, this unit begins to fail. Headlights go off, or won't turn on, or what ever they felt like doing.
Ford will not issue a TSB on this problem, nor issue a recall. In 10 minutes of internet surfing, I found 22 crown Vics with the problem and numerous Marauders, Police cars, and Lincolns. There were even a few dash fires as a result of this module failing, but Ford will not issue any kind of alert.
It is nice to see that our two watchdog federal agencies aren't watching.