[Lckitty]

My '11 sub amp was shorted out at purchase. Dealer replaced it. If I remember right on the alpine....it was a simple on/off switch in the settings. Deeper than that is crossover stuff but that is fine tuning once it is working. Should be pretty obvious if working or not. Really fills up the space in the back with more full sound. Oh, ensure the sub volume is set to 15 (max) as overall it is kinda weak. Good luck with your puzzle ;-0

 

[DominusFL]

You can move the sound to the rear speakers (they don't exist so the radio goes quiet) and then raise and lower the subwoofer level independently to hear it working.

 

[phaphaphooey]

Ditto the above. Fade the sound to the rear and crank it. In the stock configuration and setting on my car the subwoofer setting did nothing in the head unit since it was wired in the rear coax out from the head unit.

 

[KCZ]

Do you have the Alpine INA-W900? If you're replacing your sub, do yourself a favor and replace that head unit too. The Alpine INE-S920 or INE-W927 are much better and it's nearly a plug and play switch out.

 

[brgelise]

You can move the sound to the rear speakers (they don't exist so the radio goes quiet) and then raise and lower the subwoofer level independently to hear it working.

GOOD IDEA. Will do that for final confirmation. 99% sure its not working

The interface on this car is different than my 2010 so I'll assume its the newer unit. If shorted out, good excuse to just upgrade.

 

[scv]

my 12 S. Subwoofer nonfunctional(Pioneer avic x940bt). Dealer was unable to fix. Will try myself or have another dealer go at it.
If you fade all sound to rear, and increase volume to rear, should hear sound. If none, as in my case, rear speaker/subwoofer nonfunctional. Other threads note possible fuse blown/bad rear speaker amp/improper wiring from head unit. Let us know what you find: I'll post my fix when completed.

 

[brgelise]

I'll let my ex Navy sub sonar guy handle it. Yea, he's good!

 

[brgelise]

So what have folks upgraded to? Do 8in units fit? Grill cover looks like 6.5in. If I remember right, there is depth to work with and with a 2+0 plenty of room for a proper amp.. Head unit works just fine and amp chipsets are fine also.