I have a cracked sub for a car system 12''

I have a PS-12, and I had the exact same problem. The best I can tell, the amp is overheating. It's housed in what is more or less an airtight plastic enclosure, so there is no efficient way for heat to leave the amp as the electronic components heat up.
I don't know how old your PS-12 is, but mine started to click after about four years of reliable use. Perhaps older amps are more sensitive to overheating than when they're new.

Anyways, Here's how to fix it yourself, if you're feeling up to the task:
Disconnect the sub from your system and the wall. Remove the amp from the back of the unit (ten philips head wood screws around the edge of the control panel). Disconnect the amp from the speaker itself.
Next, remove the amp from its asphyxiating plastic enclosure (2 smaller philips head machine screws hold it on, one to the right of the LED power indicator, the other to the left of the power cord.
Now, the fun part. Take the empty plastic enclosure, and turn it into swiss cheese with a drill. I would recommend a large drill bit and as many holes as you feel comfortable with, because the whole point is to get as much airflow across the amp as possible. If you've got better tools to cut holes in the enclosure, feel free. Whatever it takes to open it up. Be careful of the speaker wire as you go.
As for a source of airflow, the speaker actually provides that itself. Just reassemble the whole mess, and your speaker should stop clicking.
If the amp continues to click, consider more holes. Oh, and don't worry if you crack the enclosure a little as you drill, it doesn't serve much of a functional or structural purpose, and you won't see the cracks again anyways. As long as you can screw it back onto the amp, you'll be fine.

it will cost a little bit but what I would do is find a uses part and new gasket,Did some one hit something because they dont crack much, and I hope the cranks is not bent,I hope this helps you?

http://www.rockfordfosgate.com/rftech/woofer_wizard.asp
go here put in your specs and you have your answer :]

What is your question?

No the only way to fix it would be to take it to someone. Cracked screens do not have an at home fix, plus if the backlight or bulb has shattered then you'll need a new one.

cone is cracked if you see the crack sometimes epoxy or rubber glue can wrok but Id ship it back to audiobahn if under warranty otherwise buy another one as shipping and repair gets expensive

Hi there
i beleive that underneath some dustcaps is unsealed. the dustcap in some subs encloses the motor that drives it. I would suggest getting it fixed in 1 way or another just incase. Having the motor exposed( if it is) can burn out if unattended to.
I hope this helped.
thanks jeremy

If you have a dual voice coil sub, make sure that you have the positive and negative terminals connected properly. If you have ONE of the coils wired backwards, it will cause the speaker to produce little or no sound.

Have you set the gains properly?

Are you sure the amplifier is receiving a strong signal from the head unit?

Have you tried it with a different speaker?

Fixed the problem...I just purchased another one online (from a store that has a good return problem) and will return the one that doesn't work! Cheers! :)

need to know where the crack is. Is it a shipping damage or was it cracked before?? Let me know PLEASE