I'd recommend going to ford-trucks.com and doing a search in their 6.0 forum to find you a wiring diagram of the heated seats. There is a connector under the seat where you should find a yellow wire with a light blue stripe. This wire should read 12V whenever you flip your heated seat switch on. PITA part is that you can't take that connector apart or the switch won't work, so you have to find a way to probe inside that connector.