Sub/ Amp power issue

In car entertainment: stereo; speakers; portable devices etc

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crashbanggg
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Sub/ Amp power issue

Post by crashbanggg » Thu Oct 31, 2013 6:41 pm

I have just tried to install a sub/ amp to my existing setup (Phillips CEM300 with Alpine 6x4's), however I can't seem to get power to the amp? I have connected the remote output from the amp, to the 'Subwoofer out' on the head-unit (By cutting off the plug and twisting the wires together), but still no power. Does anyone have a clue what it could be?

My only other thought would be to split the wire that is powering the Headunit to power the amp as well... or is that a stupid idea?

I'll be getting my hands on a multimeter tonight if I can use that to test anything?


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Re: Sub/ Amp power issue

Post by Nate » Thu Oct 31, 2013 6:52 pm

assuming that you have got the trigger wire connected to something that goes live when you turn the head unit on, check that the main power and earth to the amp are connected properly (particularly the earth connection to the bodywork) and check that the fuse at the battery connection is ok, and the fuse on the amp


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Re: Sub/ Amp power issue

Post by bengould » Thu Oct 31, 2013 7:42 pm

Ignoring the 4 channel amp in the middle and the capacitor you should have something like this....

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If the amp won't turn on you can TEMPORARILY bridge the Main 12v to the remote to see if the amp is at fault.


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Re: Sub/ Amp power issue

Post by mr.brown » Thu Oct 31, 2013 9:53 pm

Please don't say you're attempting to power the amp solely by using the blue lead from the head unit..



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Re: Sub/ Amp power issue

Post by Mr Funk » Thu Oct 31, 2013 10:38 pm

It's a bit confusing to read but that's what I think he's doing.


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Re: Sub/ Amp power issue

Post by crashbanggg » Thu Oct 31, 2013 11:35 pm

Sorry if I haven't explained it very well! I have power to the amp via a power cable directly from battery (only at the point at which I reattached the battery terminal was I made aware that the alarm does in fact work... I never jumped so much in my life)

The issue is, although i am 99% sure it's wired up correctly, the amp isn't powering up when the radio is turned on. As it stands, I have removed the plug on 'sub out' wire from the back of the headunit and attached it to the remote wire from the amp... Which I think should work... But it doesn't.
This is what it looked like before I chopped the plug:

Image

Il test with a multimeter tomorrow to see if the wires get any power when the headunit turns on and see how it goes from there.


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Re: Sub/ Amp power issue

Post by Nate » Fri Nov 01, 2013 1:30 am

how and to what, have you connected the earth to the amp?


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Re: Sub/ Amp power issue

Post by fonzooorooo » Fri Nov 01, 2013 10:21 am

That's the wrong wire you've chopped... That's AUDIO out to the sub... Your remote should be connected to the power antenna lead (that becomes live when the headunit's switched on, so the antenna goes up)

+1 on Nate's query about the earth too.



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Re: Sub/ Amp power issue

Post by crashbanggg » Fri Nov 01, 2013 12:15 pm

I had wondered whether that would be the issue! Il have a play once iv finished lectures.


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Re: Sub/ Amp power issue

Post by crashbanggg » Fri Nov 01, 2013 12:21 pm

And the earth is currently on the same earth as the rear lights, however I'm thinking of moving it to the rear seatbelt belt bolt bit if that would be ok/ work?


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Re: Sub/ Amp power issue

Post by crashbanggg » Fri Nov 01, 2013 3:58 pm

Hooked it up to the Ariel wire and it works perfectly, happy now! Thanks for all the help!


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Re: Sub/ Amp power issue

Post by Jack92 » Tue Nov 05, 2013 2:30 pm

crashbanggg wrote:Hooked it up to the Ariel wire and it works perfectly, happy now! Thanks for all the help!
Out of curiosity, where are you taking the audio feed for the sub from? considering you chopped the audio sub out off lol


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crashbanggg
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Re: Sub/ Amp power issue

Post by crashbanggg » Tue Nov 05, 2013 6:38 pm

Jack92 wrote:
crashbanggg wrote:Hooked it up to the Ariel wire and it works perfectly, happy now! Thanks for all the help!
Out of curiosity, where are you taking the audio feed for the sub from? considering you chopped the audio sub out off lol
The headunit has regular RCA (?) outputs as well as the cable so its run via that!


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Re: Sub/ Amp power issue

Post by fonzooorooo » Wed Nov 06, 2013 4:35 pm

If you reattach the plug (it'll be a 2 core wire - core and screen) , it's already summed mono, and is likely to have a low pass, and potentially a level control on the headunit.

Any earth is OK - as long as it's a good connection. - If it works happily how it is, leave it alone!



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Re: Sub/ Amp power issue

Post by fonzooorooo » Wed Nov 06, 2013 4:40 pm

Oooh, i see you're a part-time local too (I'm just at Coalville) ... I'm rocco-less these days, but we have a bit of a fleet of other '90s VWs - I'll give you a wave if I see you!