Boogied27

Hello guys I’m new to this and need help. I’ve never wired up an audio system with a stock radio. I have a 2013 Chevy traverse and want to add some subs with an aftermarket amp. Reading many forums I purchased a line output converter and wired it up according to the wire diagram my amp turns on but my subs don’t work. I have the line output converter wired to my rear speakers. Could it be that I need to wire the lOC somewhere else?