# WTF is yellow AMP CONT for?



## NewbieL7Q (Mar 26, 2021)

my head unit has this yellow wire labeled as "amp cont". Wtf is it for? The head unit has the option to adjust the volume on subs but I turn it up and nothing i turn it down and nothing. I think it has something to do with that wire


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## NewbieL7Q (Mar 26, 2021)

UPDATE:







A10 is the wire in question


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## THX0849 (Sep 24, 2019)

Basically it’s the constant 12v power from your battery. Connect that to a fused always on 12v source.


Sent from my iPhone using Tapatalk


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## JetBadger (Jan 4, 2021)

is most likely the "remote" wire. There can be one for power antenna and one for amp cont(rol). 

As for sub level, make sure you've connected to the correct RCAs and whether there might be some configuration for that in the head unit.

If it's a china special h/u, good luck with that. I had one, it had a sub out but no kind of control for it in the interface. Had to use the rear outs and control both rear channels at the same time with the clumsy interface for adjustments. A pile of garbage.


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## JetBadger (Jan 4, 2021)

THX0849 said:


> Basically it’s the constant 12v power from your battery. Connect that to a fused always on 12v source.
> 
> 
> Sent from my iPhone using Tapatalk


That would be the thicker yellow wire in the main loom you see in the photo, since it is working the wire must be connected. I would not connect the little one to battery+, not with any positive outcome from that


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## NewbieL7Q (Mar 26, 2021)

THX0849 said:


> Basically it’s the constant 12v power from your battery. Connect that to a fused always on 12v source.
> 
> 
> Sent from my iPhone using Tapatalk


Thanks for the info.


THX0849 said:


> Basically it’s the constant 12v power from your battery. Connect that to a fused always on 12v source.
> 
> 
> Sent from my iPhone using Tapatalk


Thank you for the information. Could you explain what purpose that would serve? The reason I ask is because the head unit is already connected to a constant 12v source and a 12v ignition source. So the head unit has power and it responds to the position of the ignition. And the amplifier is connected directly to the car battery through a 1/0 gauge wire and a 200 amp fuse. So my point is the stereo, amp and sub is getting power so what purpose would that "amp cont" wire serve? Again thanks for the info it appreciated.


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## NewbieL7Q (Mar 26, 2021)

JetBadger said:


> is most likely the "remote" wire. There can be one for power antenna and one for amp cont(rol).
> 
> As for sub level, make sure you've connected to the correct RCAs and whether there might be some configuration for that in the head unit.
> 
> ...


Thanks for the info but it's not the remote wire because the head unit has a designated blue wire labeled remote. As for the rca cables the head unit only has a single set of audio out rcaS.


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## dumdum (Feb 27, 2007)

NewbieL7Q said:


> Thanks for the info but it's not the remote wire because the head unit has a designated blue wire labeled remote. As for the rca cables the head unit only has a single set of audio out rcaS.


The yellow is a remote for the amps, the blue is for an electric aerial if it’s a joying as per the pic previously posted, you are way over thinking this, the joys of buying cheap android headunits

did it not come with installation instructions if it’s not a joying?


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## NewbieL7Q (Mar 26, 2021)

dumdum said:


> The yellow is a remote for the amps, the blue is for an electric aerial if it’s a joying as per the pic previously posted, you are way over thinking this, the joys of buying cheap android headunits
> 
> did it not come with installation instructions if it’s not a joying?


I have tried hooking up the yellow "amp cont" wire to the amps remote wire but if I do that the amp doesn't get power. So I connected the blue "remote wire to the amp remote wire and it works fine. This head unit is not a "joying" it is however from China. As for the instructions I threw them away because I have installed countless head units but I have never seen this stupid yellow "amp cont" wire. I'm over it at this point. My sub is hitting hard and it would have been nice to be able to use that sub volume setting I posted in the pic. I guess I will just buy an external bass controller and use that to control the volume of my sub. Thanks for the info it is much appreciated. Cheers!


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## miniSQ (Aug 4, 2009)

i googled it. Google says it goes to your amp, if you don't have an amp don't connect it.


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## NewbieL7Q (Mar 26, 2021)

miniSQ said:


> i googled it. Google says it goes to your amp, if you don't have an amp don't connect it.


Thanks for the input its much appreciated. However I don't believe it is for the amp. Where would I connect it? The amp has a connection for the 12v source wich goes to the battery. Then there is the ground connection which goes to the chasis. And finally the remote or antenna connection and that connects to the remote/antenna wire from the head unit. And of course the rcaS input and that connects to the head unit to. So where does the amp cont wire go? I tried using it like the remote/antenna wire but that did nothing. There is no way it could be the 12v source to power the amp because the wire is super thin. I use a 1/0 Guage wire with a 200 amp fuse to power the amp. Again thanks for your help it is appreciated.


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## NewbieL7Q (Mar 26, 2021)

NewbieL7Q said:


> Thanks for the info but it's not the remote wire because the head unit has a designated blue wire labeled remote. As for the rca cables the head unit only has a single set of audio out rcaS.


I'm starting to think it is for the power antenna but instead of the label reading "ant cont" the mis labeled it as "amp cont"


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## miniSQ (Aug 4, 2009)

NewbieL7Q said:


> Thanks for the input its much appreciated. However I don't believe it is for the amp. Where would I connect it? The amp has a connection for the 12v source wich goes to the battery. Then there is the ground connection which goes to the chasis. And finally the remote or antenna connection and that connects to the remote/antenna wire from the head unit. And of course the rcaS input and that connects to the head unit to. So where does the amp cont wire go? I tried using it like the remote/antenna wire but that did nothing. There is no way it could be the 12v source to power the amp because the wire is super thin. I use a 1/0 Guage wire with a 200 amp fuse to power the amp. Again thanks for your help it is appreciated.


can you meter it? is it constant 12v? Is it switched power? Is it nothing?


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## miniSQ (Aug 4, 2009)

NewbieL7Q said:


> I'm starting to think it is for the power antenna but instead of the label reading "ant cont" the mis labeled it as "amp cont"


But would an antenna wire be continuous?


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## NewbieL7Q (Mar 26, 2021)

miniSQ said:


> can you meter it? is it constant 12v? Is it switched power? Is it nothing?


I tested the voltage on it yesterday and i got nothing 0 volts. So I don't know what purpose it serves. I'm like %90 over it by now. I will just leave it be and buy an external bass controller and adjust the volume on my sub that way. Thanks for the help. Cheers!


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## ANS (Sep 23, 2011)

The yellow wire which is amp continuous is for powering a separate "brick" amplifier off of the radio power supply. It is not meant for high current applications. So, basically, it is giving you a continuous 12 volt out to use. If it is not working there may be a setting on the radio to engage it.


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## dumdum (Feb 27, 2007)

ANS said:


> The yellow wire which is amp continuous is for powering a separate "brick" amplifier off of the radio power supply. It is not meant for high current applications. So, basically, it is giving you a continuous 12 volt out to use. If it is not working there may be a setting on the radio to engage it.


If that was the case it would turn his amp on, albeit permenently, I have never ever seen a switchable live output on a radio... have you?


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## dumdum (Feb 27, 2007)

NewbieL7Q said:


> I tested the voltage on it yesterday and i got nothing 0 volts. So I don't know what purpose it serves. I'm like %90 over it by now. I will just leave it be and buy an external bass controller and adjust the volume on my sub that way. Thanks for the help. Cheers!


I was just going to say exactly this, if the blue remote works then all is good! Insulate it and disregard it 👍🏼


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## ANS (Sep 23, 2011)

dumdum said:


> If that was the case it would turn his amp on, albeit permenently, I have never ever seen a switchable live output on a radio... have you?


It would provide the constant connection for the brick amplifier and the remote out would still need to run to the amplifier to trigger it on and off, in turn, the amplifier would not stay on always. It is a convenience wire some of the android based and off brands have started to add.


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## dumdum (Feb 27, 2007)

ANS said:


> It would provide the constant connection for the brick amplifier and the remote out would still need to run to the amplifier to trigger it on and off, in turn, the amplifier would not stay on always. It is a convenience wire some of the android based and off brands have started to add.


Sadly android makers put all sorts of crap on hu... but even if it is that it’s irrelevant in his install, tape it and forget it, we can agree on that I hope?


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## ANS (Sep 23, 2011)

dumdum said:


> Sadly android makers put all sorts of crap on hu... but even if it is that it’s irrelevant in his install, tape it and forget it, we can agree on that I hope?


Yep, they are adding tons of "convenience items" lol. I never disagreed, just wanted anyone who was reading this to know what the intentions of the wire are. Tape/crimp cap that b**** and call it a day.


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## JetBadger (Jan 4, 2021)

Can't imagine that little 0.75mm2 or so wire providing anything of use even for a small amplifier. Eitherway it's probably just a number of similar chinabay manufacturers using same connectors and pigtails, but having different applications between units where they might make use of them or might not. Unit I had had a completely useless sub RCA output that neither worked, nor had any kind of setting available in the unit. It's just the way these are.


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## miniSQ (Aug 4, 2009)

ANS said:


> The yellow wire which is amp continuous is for powering a separate "brick" amplifier off of the radio power supply. It is not meant for high current applications. So, basically, it is giving you a continuous 12 volt out to use. If it is not working there may be a setting on the radio to engage it.


This is correct, and also what i read on google was that it is programable in the HU like you said.


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## Chillyc90 (Apr 30, 2021)

dumdum said:


> I was just going to say exactly this, if the blue remote works then all is good! Insulate it and disregard it 👍🏼


I have the same type of harness and was wondering what that wire is too, it carries no voltage off or on. I did like you and just used the blue wire to control amp turn on. That small yellow wire basically does nothing


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