Went and bought a trailer last night and no right turn signal, after trying three different trailers the same problem. Took one home and when I got home no brake or turn signals just running lights.Should have stated 2002 ranger 4.0, Test light shows no power to the plug except running lights. Checked all the fuses listed in the owners manual and the relay could I be missing something?

 

I dont have wiring diagrams for an 02, but most Fords use a trailer tow right turn & stop relay, and a trailer tow left turn & stop relay. Theres also a seperate fuse for these relays.

Have you checked these relays and the fuse???

BTW, i've been told that Ford does not always install these relays & fuse on the assembly line, so they might never have been installed on yours.

 

Thank you for the reply. The prob was at the 4 pin plug. Michigan crud ran up the wires.

 

Thanks for the update, i'm glad you got it squared away.