trailer turn signals

[surfdunn]

Been looking through the ford manual for my trailer brakes and turn signals and all I can find it 1/2 ISO relay, which is the fuse box under the hood. Can anyone help me out cause I have no clue what this means and when I hook up to any trailer, my brake lights or turn signals wont work

[humboldtstrokin']

I am having the same problem

[Farmboy444]

I havent had that prob with any of our company trucks, and the turns work fine w/o the trailer but wont work with the trailer

[twhouse]

Had that with Clifford when he first came home, fuse f9 20 amp mini in the under the hood box was blown, will not let the turn sig relays work.
'05 f250

[surfdunn]

thanks I'll check it out tonight