I replaced the stock radio in my wife's 2003 G35 sedan in 2013. I replaced it with a Dual X2DMA400 to be exact. Now that the G35 is my son's car, he has said that the subwoofer behind the back seats is not working. My best guess is this stopped working when I replaced the stock radio and no one noticed until now. Are there any special wiring needs for the subwoofer when replacing the stock radio? How can I ID the subwoofer wires if I pull the current head unit out of the dash (to check for wiring problems there?)

What I have done so far:
Checked voltage at the wiring harness near subwoofer (no voltage)
Ensured subwoofer volume was set high in the setup menu on head unit.
In the head unit setup menu, changed the SUBWOOFER setting from "subwoofer sub" to "subwoofer rear"

Any further ideas on troubleshooting would be appreciated.

 

Please look here: https://g35driver.com/forums/audio-v...ml#post5036291

Check your wiring harness and cross reference the diagram for the factory bose wiring harness and check your harness to make sure everything is connected properly. If you're not using the harness listed in that thread, your best bet is to change the harness so that it's easier to make the right connections and trouble shoot.