New amplified subwoofer installed but NO sound. Help Please.

[Rado]

Hello. I got one of those slim subs and hooked it in my 2001 X5. The problem is everything looks normal and connected and green light is on the sub but there is no sound from it at all.
Here is what i did so far:
-positive 12v to the box behind the spare tire
- negative to the bolt on chassis
- remote on to the white wire on the factory amp harness
- checked the high input wires to speakers and all phases are good
basically I followed this instructions:
http://www.xoutpost.com/electronics/...-included.html

I checked with a volt tester that there is 12V and remote on and ground working, just no sound.
Then I found this post:
http://www.xoutpost.com/articles/x5/...ctory-amp.html

and here he tapped into different wires for the speakers.
Should I do that wiring or the one on the top - I'm confused. Is there anything else I can check or do? Please Help.
The sub i got is from soundstorm lab, here is a link and there is a doc with the manual as well there: SOUND STORM | everything else is just noise

Thanks in advance for any help. I would like to get this working soon. I ordered it from amazon, so a replacement sub is on its way just in case this one is defective, but if the new one has the same problem, then something is wrong with my wiring.
Also I forgot to mention that i have the aftermarket hualingan radio unit and i'm very happy with it, since I bought it one year ago.

[mrbmwx5]

The sub you got from soundstorm lab have amplified buit in ,plus your aftermarket hualingan radio also have amplified buit in ,that is the problem , both of those unit will make your factory AMP over loaded and sent the stock AMP to safe/sleep mode = NO sound.

[Rado]

If my stock amp is in safe/sleep mode, then I will have no sound at all to all my speakers, right? But I have sound to all speakers, just the new sub does not have sound. Anyway, what is a suggestion here. Most after market HU have amps built in and you can still put separate amp and subwoofer and no problem. What should I do?

[Rado]

Problem solved. I wired all from the first link I posted and the sub had no sound. Today I wired it like it shows on the second link from my first post and boom it works. Now, I have another question - when I connect pin 1 and 2 and pin 24 and 25 to the harness that came with the sub, there is good bass, but if I only connect pin 24 and 25 to the sub there is even more bass and sounds better. Why is that?
Also, should I try to buy LOC and use the same speaker wires and connect them trhu LOC to the low level input - would that be any better or I should leave it as is.
Thanks again.

[ECS Tuning]

If the polarity is reversed that will cause a lack of quality and lower sound levels. Try switching the positions (+ and -) of your sound leads and see if the sound cleans up.

ECS Tuning

[Rado]

I already tried reversing the +/-. When all is connected per manual I get decent sound, but when I only connect pin 24 and 25 to the R+/- channel - then the sound is greater, louder and more bass. Maybe that is how it is supposed to be, but then i have the left channel +- just hanging.