16journey

I knew it was going to be something stupid lol. Is this only across the positive side or do I need to do both positive and negative?

I have a 2016 journey with the 4.3" radio screen. I decided to upgrade the speakers by cutting the speaker wires behind the radio and useing a lc7i processor to feed my amps. The radio powers up and seems to work fine however does not send audio signal. My wiring was fine and checked by a store. There is no factory amp and according to the dealership the car is showing "open speaker circuit". Any ideas what's going on and what the fix could be?