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Subwoofer and Amplifier install

95K views 69 replies 33 participants last post by  Keith (mechanic) 
#1 ·
Okay, so here we go....

First thing is to fit a remote source to turn the amp on and off with a switched live. Theres maybe a few different places to do this but the norm is the cigarette lighter/ 12v socket. If you have the Sports tourer you'll probably find one easily accessible in the boot, but for us super hot hatches, I'll cover the front.

Start by removing the panel to the cabin fusebox and the air con controls...
The panel unclips from the left hand side and unhooks from the right so give it a tug from the left...
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The flower flex will have a similar arrangement, you'll just have an added step to disconnect the power to it to remove the unit completely.

The air con controls have 2 push clips holding it in place, with the fuse panels removed, you'll be able to grab it from below and give it a tug to disengage the push clips...
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Once out, remove its connector from the rear and set aside.

Remove the gaitors around the gear shifter and handbrake (if you have a manual and not electronic parking brake). Both unclip from the rear and sides and unhook at the front, so start at the rear and work your way forward. U may need a small flat tool to help get it started, especially on the gear knob gaitor, but I managed without. Once the gear gaitor is removed, you will have access to 2 torx screws on both sides which secure the trim with the lower console control buttons.
Remove these and unclip the lower console controls. The controls have tabs that clip over lugs on the console so be gentle and start from the top at the buttons and work your way down, you may need a flat tool to help lift the tabs over the lugs as you progress...
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Once you have removed the connector to the console controls, you will now be able to remove the centre console by pulling it rewards. The console has 8 push clips holding it secure, located from centre to top of console, just remember to pull straight back because there is also plastic locator pins which may snap if you take it out skewed...
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Unclip the 2 side panels in the footwells, secured with plush clips...
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Remove the 4 screws, 2 on either side, 2 at front and 2 at rear, of the lower console and armrest using a 7mm socket...
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#2 ·
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Now lift the lower console from the rear of the arm rest and pull rearwards to unclip from the dash. There is 2 push clips at the front securing it to the dash...
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You only need the lower console pulled rearwards a little to get access to the 2 connectors at the front. The small connector is the USB, and has a button to push to allow you to pull it out. The large harness connect has a button just above the purple locking arm. Push this, lift the arm and disconnect... Hand Tire Automotive tire Automotive lighting Hood


At this point I decided I was going to take my switched live source from this harness. If your taking if from the 12v socket, the socket will just push out of the lower console giving you access to the wires. There is 3 wires into the 12v socket, black = ground, purple = switched live and yellow = lights live (only live with your lights on)

Back to our harness...
The harness cover can be removed. The black cover has tabs that fit over 2 lugs on the brown connector. Separate the cover from the connector...
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In this connector, there is a purple/blue striped wire which is a switched live. I crimped on a trimmed-down spade connector to my remote wire and pushed it into same socket as the purple/blue striped wire which was pretty secure...
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Now feed the remote wire to the right hand side of your car around the footwell, securing it with cable ties to avoid rattle.

You can now retrace your steps to put the centre console back together.

Now for the audio output source...

On the right hand side of the car, behind the dash is the radio unit.

LEFT HAND DRIVE CAR - it's behind the glove box which is secured with screws and push clips. There is 2 screws behind the side panel of the dash, with the door open, which has the air bag switch. This panel just unlips to give you access to the screws...
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RIGHT HAND DRIVE CAR - it's behind the small storage cubby to the right of the steering wheel. Open the storage cubby and at the rear, squeeze the 2 sides together to get the rear the to pass the dash completely. Then the storage cubby can be unhooked from its hinge and removed...
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The radio unit is the silver box with multiple connectors plugged into it at the bottom. The connector we're interested in is the green one. Disconnect the green connector for access...
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The 4 pairs of wires (eight wires in total) to one side of the connector is the speaker wires. The other 2, red and black, appear to power the navi 900 display on the centre console.

Solid colour = +positive, striped = -negative
LEFT REAR AUDIO- solid green and green/black stripe
RIGHT REAR AUDIO- solid white and blue/black stripe
FRONT LEFT AUDIO- solid blue and brown/blue stripe
FRONT RIGHT AUDIO- solid yellow and yellow/black stripe.

When I first connected this, I mistakenly tapped 1 rear and 1 front, and when the front was tapped, it made my tweeter cut out. Make sure you tap the rear audios signals.

Now it depends on your amplifier whether it can accept high level input, but if it can't, you'll be connecting a high to low audio signal converter to these green & green/black striped and white & blue/black stripe wires. My amplifier can accept high level audio, so I just cut down an old RCA phono cable to approx 1 foot (30cm) split the wires and crimped the ends of the bare wires so I could push them into the same socket at the existing wire sets.
My crimps needed altering a few times to get them to fit and tidied the wires with electrical tape...

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#4 ·
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At the other end of my RCA phono lead, I connected a bass/volume level control knob which has input output rca phono connectors. I plugged my custom RCA phono lead into the input and connected my main RCA leads into the output jack's. This bass level control is going to be fixed into my storage cubby for easy access and control of my bass volume...
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Now run your main RCA leads and remote power cable together to the boot, tucking the wires under the plastic trim between the floor and the doors. Remember and secure loose cables behind the dash with cable ties to avoid any rattling.

When you get to the rear seats with your cables, you'll have to lift the rear bench to feed your cables into the boot. The rear bench is secured to the chassis with 2 pretty tough push locks at the front, and hooks at the rear. The 2 at the front are at the centre of the left seat and the centre of the right seat. Stand outside the car facing the front, lean in and grab the bench with both hands between the front of the bench and chassis, with both hands on the same side of the push lock pin/loop at the middle seat side / centre of the car / inner side and tug as hard is you can. First time I did it I used a large socket ratchet to pry it off by.putting it between the bench and chassis and lifting up, but again keep it to the side of the pin/loop closest to the middle seat...
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You only need to lift one side to continue to feed your cables to the boot.

Now to the boot...
You'll need a good ground for your amplifier. I removed one of the silver hoops for strapping down and scrapped away the paint using a Stanley blade/ box cutter. Make a good job at removing all the paint so you have good contact with the bare metal. I crimped a hoop connector onto my ground wire and screwed this back below the silver boot hoop...
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If you havent done so already, which I would advise, disconnect your -negative to your battery. Connect your amplifiers fused power lead to your battery +positive terminal. Connect your remote power to your amp, then your power from battery, then your ground cable. Put your power fuse if your leaving it until last and reconnect your -negative battery...
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Get your capet back down, position your amp and sub, connect your amp to your sub with your speaker wire...
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JAMMING!

Jump in your car, start her up, set the time and date, take her for a spin to get the outside temperature reading reset and to get rid of the possible ice warning and CRANK IT UP!¡!¡!¡!
:twisted: :twisted: :twisted:

But this is just a guide not definitive instructions, every car is different... myself or no one else here is responsible for anything that happens as a result of you making modifications to your car.... Least of all vibrating mirrors or cable tie tail rattles!
:lol:

Anyway... Phase 2 will be a proper custom boot configuration, I'll post in future!

HAPPY NEW YEAR!
 

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#5 ·
Great write up Chris, so detailed and I applaud your skill and knowledge regarding how to do this as it seems very complex compared to the old days of fitting an amp and sub to a car.

It's great to have another post with details and pics on the removal of the central console.

This is one mod I won't be attempting for a few reasons:-

° I'm happy enough with the sound quality at the moment.
° the complexity scares me on a car with warranty
° if and when I decide to trade mine in for another car I don't want to have to remove it all again our sell it witch the extra equipment

Maybe if I had the 200hp model and was definitely keeping it once fully paid for I would contact you and offer to pay you to fit mine lol.

Well done mate, hopefully at the meet in June if I can make it I can hear how good your system sounds.
1.0 Turbo SRI NAV (105)
 
#6 ·
Thanks Proph, it taking a few days and a complete dash and interior tear down to figure out what the hell I was doing. There may even be a better way of doing it too. Even my custom RCA phono lead will get better connection fitted to them, I just couldn't get bullet or spade connectors to fit so I kept cutting 'em up with tin snips to make them fit... I'm looking into better crimp pin connectors... But I've no patience waiting for them to arrive... and I've been at this for 3 days now!
Like you, I don't really want to void my warranty, so everything has to be reversible without cutting and splicing wires, and quickly removed if need be.

Thanks for the comments, I had to post this, I just know there will be plenty of good people out there with awesome cars who need this modification know how!

Thanks again!
 
#8 ·
Thanks Cornish, TBH, I seen your level control in your storage cubby and thought.... I'm having that! :lol:

I bought a multi meter from screwfix for £10 and every free connection that didn't have a fuse behind the powerflex seems to be constant live, no switched, which was a bit of a bummer, so the lower console harness seemed to be the best bet.

Also, for the life of me, I couldn't remove the lower console completely at all! I couldn't get it passed the handbrake lever. I removed the rear panel which holds the dual rear usb, but still, the handbrake lever got in my way and I couldn't see how to remove the lever or separate the armrest from the lower console... if it even does? Not that I needed to remove it but when your that far gone, you want to go all the way for future reference... Say for handbrake adjustment?
 
#10 ·
Anupanu said:
Great posts, but did you look in the fusebox in the boot for switched power?
Agreed...
...However....
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...I couldn't find the rear fuse box as described in my manual!!!...Typical huh? So who out there is missing their rear fuse box? Is it engine/model specific? Is it Model Year specific?
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Perhaps a rear interior tear down will reveal one, but I'm not convinced!

I plan on building a custom deck to house the sub, amp and an additional aux socket, so I'll try pin point a closer rear source then. Even in the battery compartment I'm unsure I'll find one, but i'll certainly try! Open to suggestions everyone!!!
 

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#11 ·
The rear fuse box is missing unless you have the elite or any of the options like heated seats, steering wheel, parking sensors etc that are in that fuse box in the manual, I looked for it before to run a boot 12v
 
#13 ·
I wish....I diff sounds research into adding my own rear fuse box but seemed hard, then I looked into a 12v run from battery with a relay to control it...in the eggs I went with the basic option of multi plug from the original 12v stored under the passenger seat assigns wire hidden along the rubber moulding.
 
#16 ·
Hey

Mine is opel and left hand drive car
I think my radio is located behind the glove box
But it's not the same connectors and colors as in pictures in your guide, mine is a 7 "r 4.0 intelliLink
Believe it is the brown connectors for my speakers, What do you think ..?

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This is a picture of the side of what I think is the radio
Sorry it's stuck so i can not take a better picture

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#17 ·
Wanted to chime in and say thank you for this guide.

I have replaced my front speakers with some nice Focal jobs and immediately ran into problems that the stock amp could not drive them despite them being 4ohms as the stock ones, all sorts of odd clipping of the low end at any volume.

Using a Pioneer GM-D1004 amplifier I was able to chop into the front channels and bypass the useless stock amp.

Sounds much much better.

My system is the same as the above poster, the wires are the same as for the Nav900 but they are located in the opposite plug and in different positions. The brown plug, speakers all along the rear of the connector as you have photographed it and coloured as this guide has them listed for channels.

WIll pop some pictures up later.
 
#18 ·
Hi,

I have a high-end sub, which I would like to carry over from my Astra G into the new K. Does anyone know maybe how low-level outputs can be obtained from any of the radio harnesses? My amp does not take high level input and to tell the truth for this level of D class amp I would not want to use high level conversion, would be nice to have low level output somehow. If not availalbe at all can the factroy amp and sub be installed to a Navi 900 system afterwards, like at home or at a dealership? I mean is there a harness already built in for that, where is the place of the factory sub within the car??

Thanks.
 
#25 ·
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How about those tweeters in dashboard?
Anyone know how to replace those, it's only 4 sets of speakerwires, shouldn't it be some sort of crossover installed? Or is it some sort of dsp in stereo, but regardless it's only 4 sets of speaker wires, anyone that have changed speakers and can tell how they did with the crossover that comes with the aftermarket speaker+tweeter sets.
 

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#26 ·
Exactly what I've wanted to do to mine.. Thanks for the how-to!

I've been planning to (but haven't had the time) replace the factory speakers with something more punchy. I can't even get the volume up 3/4 without the speakers either cracking or becoming muffled/no punch. Have you upgraded your speakers too?
 
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