Although the student reference is one of the many pubs I've recently read, most of the text was from the Service Manual.
It's hard trying to nail down what is actually going on with the RKE, SKREEM, PCM, BCM, and Central Locking System.
They are all interrelated to some extent and not much documentation.
Also, along the reading, I found that the FOB RKE has a range of 20 meters (66 feet), that's a pretty good distance from the halo.
But I don't think the halo is the RKE's receive antenna.
When I replaced my SKREEM, there was a second 2-wire connector next to the halo connector that looked like its twin. I'm betting that the leads went to the RKE receive antenna.
Wish I had traced it out when I had the dash out...

BTW: Although I'm a newbie (got my Crossfire in SEP '18), I did spend quite a few years as a Systems Engineer and Software Engineer before turning Educator (Not much software work in Pensacola, but a lot of Training/Education opportunities and there is the sugar white sands at the beach.)
Also, wish 35 years in radio under your belt I'll bet you know the world of Pentodes, Triodes, Diodes and solid state components (Npn, pnp) etc. that I started out with.
HAM License KR4BY

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