From with the subwoofer Factory what wires are the positive and negative going into the speaker from the amp

Replaced all speakers and wanted to replace head unit as well but there was one plug that wasnt compatible with my new unit. Everything else fit after splicing all the wires except this one plug. Its the smaller one in the attached picture. Didnt fit the new head unit and im not sure what it is, assume its a power source since new head unit didnt power on without that plugged in.

Well the other day my sound just completely stopped working. It won’t let me change through Sources, and when it “plays” CD’s, or USB Music, the time ticks as normal and even goes to the next song and everything but no sound at all comes out. I did the Speaker Test and all speakers seemed to have tested fine as normal. I removed my ACM today and now that I’m looking at it im just not sure of what it could be because it looks fine. Is there any blueprints or reference pages on the actual layout of the ACM model main board? Just to help kinda guide me around that board which is loaded with stuff. I’d love to hopefully fix the issue without having to spend money. Any help or advice? Thanks A lot, Go Bucks!