Hey guys need your help please! I replace my factory radio with an aftermarket most of the speakers are working except the one in the back that's attached to the amplifier how do I get it to work.. or what did i do wrong or didn't do?

 

you need to search brotha! all this generic info is out there. to help get you started, use crutchfield for a radio replacement. they will literally give you and tell you everything you need for your exact scenario. and 2nd you need to reseach around here about the rear sub not working. its a common thing. look for sub cut out. its a new relay you will have to solder to the amp. if you sub is cut out and you have bose that is probably the case.

you need to be way more specific around here to get any help, we dont know your year, your stereo etc. good luck. all the info you need is around here and crutchfield