have a 2004 fi50 4.6 i was trying to hook up camper, but no running lights. so i messed with trailer connection and fuses, but now truck wont start. I have full battery, lights, ignition tone, but

Hmm. Interesting. I fail to see how 'messing' with trailer connection could cause a no start. But what stands out is you said , quote, "messed with fuses?" Make sure you have not enabled some anti theft device when you fooled around in the fuse box, especially if you were in the underhood power distribution center relay/solenoid It is possible to check OBD codes without it running, the fault codes are stored. Buy or borrow a scanner, write down the codes, and bring them back here please. One of of will help you decide what to do next, You may need to re program the key transponder

you have same problem like me messing with turn signals do what David said do what david said good luck

ended up being a 30 amp fuse that was blown, in the manual it said towing package and battery charge. thanks for all your help