I had the vehicle security system (VSS) addon part # DT4Z-19A361-A installed last week on my 2013 Edge SE. It consists of a little black box and a pretty hefty T harness. Plugging it in is trivial. To properly secure the wire harness with twist ties you will need to work under the dash and find a good spot to tie it up to. My guy ended up putting the module just behind a little removable plastic trim panel outboard of the emergency brake, and the new OBD plug is now up high on the footwell.
Here are the instructions, minus the fluff:
1. Remove OBD from its retaining clip, and plug into T harness.
2. Plug T harness base connector into VSS.
3. Turn key on 8 times fast to train the VSS
4. Twist tie harness out of the way. Remember to leave the OBD plug and the VSS sensitivity knob accessible.
The full instructions are on this thread:
The harness is heavy enough and stiff enough that the little clip for the original OBD probably can't do the job for the new OBD plug with its new wire harness attached.
The picture in the instructions doesn't really make much sense. Perhaps somebody more patient can do a better job.
Getting a dealer to do it is a challenge. I bought the part online, installation included, from a local dealer. Installation was priced at $20, probably wrong, and the dealer wouldn't honor the deal. Their estimate was 2 hours, $300, equally wrong, but nobody seemed willing to digest the instructions. Another dealer quoted $550 just for labor. So I just took the part home.
With zero car repair cabability I had the part plugged in, trained, and checked out in 10 mins. I got under the dash to secure the wire harness, but quickly got vertigo, not unexpected. I took the car to my dealer, who was nice enough to loan me a tech for 15 mins to do the twist ties. Presented with a simple problem, instead of an open ended issue with a part they've never seen before, the dealer did the right thing. No charge.
I don't know where the sensitivity knob is set. Probably in the middle. The alarm gets set off if I try to open the driver door or bang on the window. It is immune to rocking of the car. It has dual sensitivity, high and low.
Here is the funny part. I am the OP on this thread, which started when I locked my car leaving the tailgate open, and got my golf clubs stolen. Please forgive me for shifting into outrage mode, but
THE NEW VSS STILL ARMS WITH DOORS OPEN!!
That's right. It will arm with a door and the tailgate open. However, if you open another door by manually unlocking, the alarm will go off. I have only another couple of years with this car, so I probably will stick with it.