I dont know what LOC stands for but I've got the standard system as well and added the factory sub from off of ebay.

I just cut them loose from the factory wiring on the sub box and wired them in series and ran them to a small amp I have tucked into the driver side rear cover area.

I'm just waiting until the two tiny subs finally blow before I cut in a hole a for a single 8" sub. they cant take a lot of power.