I have a 2013 f150 and was trying to take the boat out today but my lights on trailer won't come on. Figured out its my truck by pulling a buddies truck to boat a d lights turn on fine. I got a little light tester that plugs into truck to test lights and I have nothing ... What fuses should I start at??? Fuses in truck or fuses by motor? My manual got lost.... Lol

 

Check in your glove box and see if there is a bag in there with a couple fuses/relays in it . Might be a pigtail for the tailgate too if you take it off. Do t remember offhand which slots they go in but if you do a search on here it should come up

 

My 2013 has the same issue althought my brake lights and signals work , But I have no marker lights and yes it is most likely the fuses under the hood ... There is a relay , of which mine had none so I robbed the one from the power steps I dont have as for fuses I used one 30 amp from the rear defroster I dont have but the marker lights still dont work ... On the square fuse I cant tell weather its good or not ... not to mention were the heck do you buy new ones . If your truck didnt come with the tow package wont find the fuses in your glove box , thety dont come if you dont have the package ...BS Most people use trucks to tow abnd they should come ready to tow fuses in tact.. Burns my *** ... as much as these trucks cost they need to be ready to do the basics when they leave the aassembly line Check out this schematic it has the tow stuff highlighted

 

I have a 2013 FX2 that bag from the glove box is still sealed in a drawer in garage and my trailer lights still work with either 4 pin or 7 pin.

 

The bag in your glove box contains fuse and relay to charge your trailer battery while you drive that is all