If so behind drivers rear tire at the bumper there will be a small ford electrical connector (cheap quality) 3 wires from the body and 2 to the bumper (those 2 go to the license plate light) The 3rd from the body is fog (if you get the dual OEM switch and turn it on in forscan). I installed a 4...
I am using a obdlinkEX cable as well as was having the same issue. I set up a new profile just in case and set it to RTS relay and this fixed my problem as well.
I've noticed on numerous threads everyone keeps fighting this with Forscan. Some may have got it working but I used this Harness from AutoStop eliminator and it was an easy install and will stay on whatever setting you last left it on. Yeah its a 100 bucks but saves a lot of headache...