73828793

i installed an aftermarket headunit today and i cannot get the center speaker to work with the new radio. i used a wiring harness adapter kit and noticed it doesn't make use of all the factory wires on the plugs. does the center speaker amp needed to be manually grounded? also this is a non bose setup. any help will be appreciated.

P.S. i'm not a newb and i searched many different terms to no avail.