Rear subwoofer

Hi all again I got no sound from my subwoofer I've had a amp guy out today to take a look at it and he seems to fink the amp is ok the cd changer isn't connected as I've fitted a new radio with Bluetooth for music he said there's power to the sub all the time so it may have a digital signal from the head unit to switch it on and off can anyone confirm this please

hi mate, if you have changed the Head Unit then thats yr problem.. the speakers in your RR have their own amps and are fed Line level signal, and not speaker level..
am sure someone else will have more info on this...

Yer cheers mate have read older posts and found the prob and possible fix