Did a fast google and search here, as a disclaimer, but I may have failed at it.

Someone modified the speakers and sound system extensively on the car I'm working on. I can't make hide nor hair of WTF they were doing after working on it since this morning. At all.

Anyone have a schematic or diagram of the stock layout handy?

 

did you check the FSM and wiring diagrams in the FAQ? if they "extensively" modified the sound system, odds are its not using any of the factory wiring. at least it shouldn't be.

 

Annnd thank you, you explained my problem in a single sentence.

I was expecting them to at least route through factory areas, which would explain why I couldn't understand what was going on when I was reading the FSM.

I'm tearing all this crap out and just rewiring it according to factory diagrams.