I have the convenience package. I guess I'll have to go back into the quarter panel and look for a loose connector. I was thinking of picking up the sub off ebay as I upgraded my headunit to an android auto one.
I did it this last summer and it's working phenomenal. Let me know if you need any help.
I have a 2012 HB and it was not prewired for it. I was able to harvest both connectors from another car and the sub from the same car.
I'm not sure if any car came prewired for the sub if the sub was not actually there...you might look. My suggestion is to take the radio out and look behind the connectors. If you don't have the sub wiring coming out from the radio, then most likely you don't have an extra connector in the trunk.
let me know if you have any questions.