Issues with installing a subwoofer

[ukrms6]

I'm installing a mono amp for an aftermarket sub in a mazdaspeed 6 using the Line-Out Converter(LOC). How I can tap into the amp/sub wiring in the trunk using the LOC? I been trying all day to accomplish this and its not working. The amp is turning on, meaning I got the remote wire properly, but I'm not receiving any signal. Possibly I didn't hook the LOC up properly? Any advice will be helpful.
Thank You.

 

[zinger002]

why use a loc?

just use the method showed in the how to considering you already have a low level signal going to that little amp under the sub.

 

[ukrms6]

because i already have a loc, and it seems easier to do. Can the LOC method even be done using the wires going to the amp/sub in the trunk?