no turn signals in tow plug I added?
 

2013.. added a trailer hitch and added a 7-post plug and then plugged it into round plug under car by spare. I also added brake control up front and plugged it into factory plug under dash. I never hooked up a trailer but I do get test light to light when apply brakes- and I get AP (aux power) terminal to light as well as tail lights.. but neither R or L directional terminal light the test light?

Since your Durango did not come with the tow package originally, you probably need to visit a dealer and have them enable the tow connector via their scan tool. The trailer connector turn signal signals are controlled via the TIPM and since there's no clean way to upgrade to a heavy-duty flasher, you probably want the feature turned on via the TIPM to keep from having a hyper flash issue.

-Rod

Excellent point. My '13 R/t came completely equipped for towing, except no hitch. Had my local dealer install the hitch. He told me they had to go into the "system" to tell the car and Dodge that the car now could tow.

Just curious....what does 'completely equipped for towing' mean?

For some reason known only to Dodge, my '13 R/T (and all others of that year), had all the factory towing equipment, except some didn't have the hitch itself. All the wiring was there. As you can see from the attached build sheet, the car has a 220 amp alternator, trailer sway damping, heavy duty engine cooling. and rear load leveling suspension. All items included in the factory tow package. So why not the hitch itself. I can only speculate that the designers of the R/T package wanted the car to be sleek. Hence the body-colored cladding, no roof rack, no DRL's. My build sheet actually has a roof rack delete code. Again speculating, they were probably built on the same line as the V8 Citadel's. So it was easier at the beginning of the build to keep the trailer items in the mix than try to delete them. It was easier to delete the roof rack. The rear bumper cover actually was marked on the inside where to cut it for the installation of the hitch. I could have probably installed it myself, but I would still need the dealer to update the TIPM, as SHO ROD so correctly pointed out.