How To Install A Sub In A G sedan Using Stock Bose System
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Ok I have a 2003 g35 sedan with stock everything. I followed the instructions and now my speakers are very quiet. I have to turn it up to at least 20 to be able to here it where as before 10 was loud enough. What did I do wrong? Amp is getting power, but subs aren't making any noise at all and speakers are very quiet
Last edited by Zmeyer77; Oct 2, 2017 at 10:58 PM. Reason: Need to add more info
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if all is good, break out a test light or multi meter and start looking for a wire that has power when you want it (key on, better if only comes on when radio on but don't think that's gonna be an option without ripping into the dash behind the stock headunit), and is off when you don't. tap into that wire for your remote wire. And remember to fuse that wire if you're going to have to run it in such a way that it may chafe on bare/sharp metal with the potential of grounding out.
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Ok I have a 2003 g35 sedan with stock everything. I followed the instructions and now my speakers are very quiet. I have to turn it up to at least 20 to be able to here it where as before 10 was loud enough. What did I do wrong? Amp is getting power, but subs aren't making any noise at all and speakers are very quiet
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From: NY
Hey guys I have a 06 g35 sedan with factory bose interior, I'm planning on installing aftermarket sub/amp for extra bass ,I'm reading that I have to tap into the factory sub or rear speakers And I believe I would have to disconnect the factory bose sub, can i still control all four factory speakers from the BOSE Unit? ,I'm not to good with music also would I need to take out my actual head unit to connect anything? thanks
Last edited by SilverSurfer01; Dec 12, 2017 at 07:41 PM.
Would not need to take out head unit. Very simple if you have a stock sub. Unplug the sub, plug wires into a line converter which will convert those to pre-amp inputs.
Some amps will even take line level inputs directly (line level means speaker wires)
Some amps will even take line level inputs directly (line level means speaker wires)
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From: NY
I read on another thread that that my rear interior speakers would be disconnected? Correct me if I'm wrong, also thanks for the super fast reply
Although I haven't done this on a stock bose setup, just non bose, I believe the sub wires themselves would not be attached to any of the speakers at all. That would be some funky wiring. Correct me if I'm wrong someone, but that doesn't make sense. Go take a look and you should see just 2 wires attached from the sub coming from the amp
Hey guys I have a 06 g35 sedan with factory bose interior, I'm planning on installing aftermarket sub/amp for extra bass ,I'm reading that I have to tap into the factory sub or rear speakers And I believe I would have to disconnect the factory bose sub, can i still control all four factory speakers from the BOSE Unit? ,I'm not to good with music also would I need to take out my actual head unit to connect anything? thanks
I'd recommend not using the factory sub anymore, but physically removing it is fairly involved, as you have to remove the rear deck interior panels (and the rear c-pillars to get those panels out) to get the factory sub out. It's worth it if you're comfortable removing parts like that, but otherwise, leave it so you don't break anything along the way.
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For an aftermarket sub, you're going to have to run power wires to the trunk, that's going to be the biggest task. Beyond that, you can tap the signal wires going to the factory subwoofer, run them through a line output converter, and send that to your new amp. All the speakers and factory sub can continue to work just as before.
I'd recommend not using the factory sub anymore, but physically removing it is fairly involved, as you have to remove the rear deck interior panels (and the rear c-pillars to get those panels out) to get the factory sub out. It's worth it if you're comfortable removing parts like that, but otherwise, leave it so you don't break anything along the way.
I'd recommend not using the factory sub anymore, but physically removing it is fairly involved, as you have to remove the rear deck interior panels (and the rear c-pillars to get those panels out) to get the factory sub out. It's worth it if you're comfortable removing parts like that, but otherwise, leave it so you don't break anything along the way.
Thanks for the respons
Last edited by SilverSurfer01; Dec 16, 2017 at 10:32 PM.
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I saw the write up for the coupe, figured I would throw one up on how I did my '04G 
Figured I would post up a little "How to" seeing as how the beginning of the installation, going through the firewall, is the hardest part for some when it comes to doing an amp install.
This isn't a super detailed write up, I'm going to assume you are somewhat handy with basic tools and aren't afraid to get your hands dirty.
Ok here we go
Tools I used:
Plastic pannel tool
Screwdriver
Knife
wire strippers
solder and soldering iron
Electrical tape
Parts needed:
Amp kit w/ RCAs
Line out converter (LOC)
Break open you shiney new amp kit. I just went with the power kit because I already had RCAs:
Attachment 236057
Take the battery cover off
Attachment 236058
All the covers come off by popping the middle of these up then pulling them out
Attachment 236059
Attachment 236060
Then take the cabin filter cover off
Attachment 236061
This gromet with the mass of wires going in it, that's where you are going to feed your power wire and any other wires you may need to run in the future. You can already see the hood pin/tach/siren wires coming out for my remote start/alarm.
Attachment 236062
Make an "X" in the rubber gromet with your knife, and feed the power wire in about 2ft.
Attachment 236063
Open the front passenger door and remove the lower trim that runs along the door sill and then the kick panel
Attachment 236064
Attachment 236065
Attachment 236066
Stick your head in the foor well and look up towards the gromet. There is your power wire.
Attachment 236067
Once all your wire has been pulled, slide the passenger seat all the way forward and tilted.
Attachment 236068
Open rear passenger door and pull up the lower trim along the door sill
Attachment 236069
At the bottom of this panel are two clips, one per side. Pull each side straight back towards the other side of the car and the bottom should pop loose.
Attachment 236070
Attachment 236071
Go back up front and start tucking the wire all the way to the back seat. Carpet is attached to the door sill by plactic loops that go over white clips which is what holds the plastic trim to the car.
Attachment 236072
Once you get the wire to the back, take a look at where the bottom of the rear seat meets the carpet. You will see black plastic hoops. To get the rear seat up, pull the loop towards the front of the car and pull up on the seat. Don't try pulling the hoop up with the seat as it's attached to the car.
Attachment 236073
With both sides loose, pull the seat towards the front of the car to give you some space to feed the wire up with your hand. The seat doesn't have to come all the way off, you just need some space for your hand. The back of the back seat(the part that reclines, I had no idea my seats did that and was so amazed) has insulation behind it. Make sure when you feed the wire, to pull the insulation up as you pull on the upper back part of the back seat as you feed the wire up towards the trunk. If not, the wire will be between the seat and insulation and you will not be be able to see the wire or pull it.
Attachment 236074
Now that the wire has been fed up towards the trunk, crawl in the trunk and pull back the bottom carpet, and then pull up on the back panel.
Attachment 236075
Once that's done, you should be able to see the wire
Attachment 236076
Now your power wire is in the trunk
Now to install the line out converter (LOC). You have to pull down the top plastic trunk panel in order to expose the factory sub and amp. Pop out the little black buttons the same way you did the ones under the hood. There are about 6 total. Once they are all out, the panel should flop down like a door because it is attached at the back.
Attachment 236077
After you drop the panel, you will be able to see the sub
Attachment 236078
.....and the amp
Attachment 236079
Unplug the brown plug attached to the sub, pull the black sheath covering the wires, you should see a black wire and a white wire
Attachment 236080
Grab your line out converter
Attachment 236081
Now twist the (+) together(no stripe), and then the (-) together (w/black stripe). On this particulat LOC, you don't need to use the two brown wires.
Take the LOC, connect the (+) to the white wire, and the (-) to the black wire. Once you have made your connections, do not plug it back into the sub.
Attachment 236082
Move over to the amp now and unplug the two plugs on the left side of the amp. You will only need to get to the black plug but it's alot easier to work if both are unplugged
Attachment 236083
Pull the black sheath back and look for the green wire with the white stripe. That's the amp turn on wire. Take the blue wire that came with the amp kit and connect it to that wire. This is what is going to be turning your aftermarket amp on. Now plug everything back into the amp.
Run your RCAs and amp turn on wire back and down to the bottom of the trunk.
Attachment 236084
Now for your ground. Pull back the back panel like you did for the power wire, scrape/grind off paint until you get to bare metal, and sink two screws into the connector. Why two? If you attach such a large wire to thin metal, it is easy for it to start to rotate as the car bounces around down the road. That can shake the ground loose and cause your system to cut in and out. by sinking two screws into the terminal, you can help reduce that your ground will come loose. It's best to look for an existing bolt to use, but I didn't find one in the area where I would be mounting my amp.
Attachment 236085
At this point, I leave you to mount the amp, and make your connections to what ever sub/amp combo you have chosen, as the hardest part is over with. I'm running a 10" Type R with a 500w Alpine amp and it sounds pretty good! There is a serious need to have sub volume control, so for now I just have all the settings on the amp turned down. Will I be replacing my HU, yes and very soon. I was just bored on thanksgiving morning and needed something to do
Figured I would post up a little "How to" seeing as how the beginning of the installation, going through the firewall, is the hardest part for some when it comes to doing an amp install.
This isn't a super detailed write up, I'm going to assume you are somewhat handy with basic tools and aren't afraid to get your hands dirty.
Ok here we go
Tools I used:
Plastic pannel tool
Screwdriver
Knife
wire strippers
solder and soldering iron
Electrical tape
Parts needed:
Amp kit w/ RCAs
Line out converter (LOC)
Break open you shiney new amp kit. I just went with the power kit because I already had RCAs:
Attachment 236057
Take the battery cover off
Attachment 236058
All the covers come off by popping the middle of these up then pulling them out
Attachment 236059
Attachment 236060
Then take the cabin filter cover off
Attachment 236061
This gromet with the mass of wires going in it, that's where you are going to feed your power wire and any other wires you may need to run in the future. You can already see the hood pin/tach/siren wires coming out for my remote start/alarm.
Attachment 236062
Make an "X" in the rubber gromet with your knife, and feed the power wire in about 2ft.
Attachment 236063
Open the front passenger door and remove the lower trim that runs along the door sill and then the kick panel
Attachment 236064
Attachment 236065
Attachment 236066
Stick your head in the foor well and look up towards the gromet. There is your power wire.
Attachment 236067
Once all your wire has been pulled, slide the passenger seat all the way forward and tilted.
Attachment 236068
Open rear passenger door and pull up the lower trim along the door sill
Attachment 236069
At the bottom of this panel are two clips, one per side. Pull each side straight back towards the other side of the car and the bottom should pop loose.
Attachment 236070
Attachment 236071
Go back up front and start tucking the wire all the way to the back seat. Carpet is attached to the door sill by plactic loops that go over white clips which is what holds the plastic trim to the car.
Attachment 236072
Once you get the wire to the back, take a look at where the bottom of the rear seat meets the carpet. You will see black plastic hoops. To get the rear seat up, pull the loop towards the front of the car and pull up on the seat. Don't try pulling the hoop up with the seat as it's attached to the car.
Attachment 236073
With both sides loose, pull the seat towards the front of the car to give you some space to feed the wire up with your hand. The seat doesn't have to come all the way off, you just need some space for your hand. The back of the back seat(the part that reclines, I had no idea my seats did that and was so amazed
) has insulation behind it. Make sure when you feed the wire, to pull the insulation up as you pull on the upper back part of the back seat as you feed the wire up towards the trunk. If not, the wire will be between the seat and insulation and you will not be be able to see the wire or pull it.Attachment 236074
Now that the wire has been fed up towards the trunk, crawl in the trunk and pull back the bottom carpet, and then pull up on the back panel.
Attachment 236075
Once that's done, you should be able to see the wire
Attachment 236076
Now your power wire is in the trunk
Now to install the line out converter (LOC). You have to pull down the top plastic trunk panel in order to expose the factory sub and amp. Pop out the little black buttons the same way you did the ones under the hood. There are about 6 total. Once they are all out, the panel should flop down like a door because it is attached at the back.
Attachment 236077
After you drop the panel, you will be able to see the sub
Attachment 236078
.....and the amp
Attachment 236079
Unplug the brown plug attached to the sub, pull the black sheath covering the wires, you should see a black wire and a white wire
Attachment 236080
Grab your line out converter
Attachment 236081
Now twist the (+) together(no stripe), and then the (-) together (w/black stripe). On this particulat LOC, you don't need to use the two brown wires.
Take the LOC, connect the (+) to the white wire, and the (-) to the black wire. Once you have made your connections, do not plug it back into the sub.
Attachment 236082
Move over to the amp now and unplug the two plugs on the left side of the amp. You will only need to get to the black plug but it's alot easier to work if both are unplugged
Attachment 236083
Pull the black sheath back and look for the green wire with the white stripe. That's the amp turn on wire. Take the blue wire that came with the amp kit and connect it to that wire. This is what is going to be turning your aftermarket amp on. Now plug everything back into the amp.
Run your RCAs and amp turn on wire back and down to the bottom of the trunk.
Attachment 236084
Now for your ground. Pull back the back panel like you did for the power wire, scrape/grind off paint until you get to bare metal, and sink two screws into the connector. Why two? If you attach such a large wire to thin metal, it is easy for it to start to rotate as the car bounces around down the road. That can shake the ground loose and cause your system to cut in and out. by sinking two screws into the terminal, you can help reduce that your ground will come loose. It's best to look for an existing bolt to use, but I didn't find one in the area where I would be mounting my amp.
Attachment 236085
At this point, I leave you to mount the amp, and make your connections to what ever sub/amp combo you have chosen, as the hardest part is over with. I'm running a 10" Type R with a 500w Alpine amp and it sounds pretty good! There is a serious need to have sub volume control, so for now I just have all the settings on the amp turned down. Will I be replacing my HU, yes and very soon. I was just bored on thanksgiving morning and needed something to do
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Posts: 8
Likes: 2
From: VA
bought n Japan, shipd 2 Hawaii then VA:2003 Black on Black G35 Sedan w/Sport w/Bose w/window sticker
O.E.M. sub replacement in the O.E.M. location needs reverse phase (180° from 0)
It is an 8" sub, also you will want to reverse the subwoofer's phase 180° when using the O.E.M. subwoofer location with an aftermarket subwoofer.
Uhmm .. What if some idiot accidentally cut the amp turn on wire . Then what ?
I Did . Now my amp won't turn on & I'm not getting any sound out of my speakers . I know it's not the amp because I touched the positive & remote together on the amp & it turned on .. Altho I still wasn't getting any sound though .
