The fuse box for the trailer lights are under the hood (drivers side). Have to look in your owners manual to find the correct fuse.
If the blinkers work then your taillight wiring is bad.
I was looking at the 2000 Ford Windstar Owner Guide and it shows : Trailer towing requires the optional trailer tow electrical package " may require use of an additional medium duty trailer tow option package "
Ford F350 Super Duty Dually
with a screwdriver.
The 2014 Ford F-250-Super-DUTY is 6 ft. 7.9 in. (79.9 in.)12.5K Trailer Hitch wide.
Remove the old bulb and look on it's side. The # is listed there.
remove two screws, remove tail light, remove bulb. reinstallation is the reverse of removal.
On a 2000 Ford Mustang : The fuel pump inertia switch is in the trunk , behind the trunk liner on the drivers side , near the driver side rear taillight ( there is an access hole through the trunk liner )
You can buy a trailer wiring kit that plugs directly into your Explorer taillight harness. It has everything you need, including directions, so that you don't need to be concerned about what to splice into. Check with any RV dealer or places where boats and trailers are sold.
From the inside.
On a Ford Freestar : ( NO ) * according to the 2006 Ford Freestar Owner Guide , up to ( 2000 lbs if the factory trailer towing package is installed )
you unscrew it and take it off.