Just picked up a 2019 Ranger and trailer. Hooked up and drove straight home. When I went to back it up, the breaks locked. After further investigation I noticed that the running lights weren't working either. I read about Fords having some electrical issues with Ranger trailers but my 2017 Ranger was just fine with this truck. Thinking it may be the trailer (as the previous owner did switch out the plug), nope, hooked my son's Toyota up to it and everything lit up like a Christmas tree. Checked every fuse on my Ford and none of them were blown. Any ideas?