Find the high pressure oil sensor right behind the HPOP, on the driver side head, and unplug the harness. If the harness plug is full of oil, leave it unplugged and try cranking the truck. If it cranks, you have found your problem. Replace the sensor and either clean or replace to plug and you...
Take the Hayes unit off. The integrated control on the F250 has the same capability, and is much more sophisticated than the Hayes unit. Additionally, I believe that if the Hayes unit activates while hooked to the F250, it will disable the F250's integrated brake controller until you squeeze...