...Without running new wires!
I searched the forums prior to attempting this, and found lots of back and forth discussion but no definitive step-by-step, and in fact most people suggested running completely new wires from the head unit to the rear speakers.
I agree that this is the cleanest way to do things, but for those of us that don't have the time, patience, wires, or are JUST TOO DAMN LAZY to do this, here's a simple alternative:
1. Pull back the driver's side rear trunk area carpet/paneling. There are a few clips, plus you may have to take off the black plastic trunk lip guard (4 screws and 2 clips). It also helps to pop the speaker grille and take out the 2 screws holding the surrounding plastic in place. This is just so you can pull the paneling back farther.
2. There's a short metal cylinder about 4" across bolted just behind the speaker (towards the rear of the car). There's a white harness plugged into this from the speaker side. Release clip is on the bottom of the harness. Pull the harness out (it's in there real nice, I had to use pliars).
3. Clip and join the following wires:- DARK GREEN to BROWN/WHITE- RED to BROWN- PURPLE to AQUA/YELLOW- PINK to AQUA/WHITE
4. Test and put everything back. All done.
For wire joining I just stripped, twisted, and covered in heat shrink tubing and electrical tape. I simply could not be troubled to solder. ;D
Wire colors may vary, since mine is an SE and some of the colors in base models are different I hear. If they are, all you have to do is check behind your head unit to find the colors (and under the speakers if those wires are different as well).
I have a Fastback. Coupe is probably different.
Result? Insanely better sound from the rear, especially with decent speakers and head unit.
Successful S13 rear factory amp bypass
-
Timeless240
- Posts: 152
- Joined: Mon Jul 26, 2004 5:12 am
Yo Yorb! Thank you so much! When I first installed my MB Quart 4x6s in the rear, i was somewhat underwhelmed by their performance. Now I know what was holding them back!Here are some pics or the mod:
As you can see, there is that cylinder that Yorb was talking about-->
Here is a close up shot of the wiring harness that I could NOT get out.
Since I could not get the harness out cleanly, I just cut ALL of the wires; not only the 8 that I was going to connect together, but the 3 others that I couldn't identify. So I just stripped and twisted up the corresponding pairs and left the other three blowing in the wind.-->
Here's a shot of them taped up-->
By the way, it's been about a year since I installed the head unit so I forgot what all the wire colors represented. Does anyone know what those other 3 wires are for? The blue one, the black one, and the light green one?
As you can see, there is that cylinder that Yorb was talking about-->
Here is a close up shot of the wiring harness that I could NOT get out.
Since I could not get the harness out cleanly, I just cut ALL of the wires; not only the 8 that I was going to connect together, but the 3 others that I couldn't identify. So I just stripped and twisted up the corresponding pairs and left the other three blowing in the wind.-->
Here's a shot of them taped up-->
By the way, it's been about a year since I installed the head unit so I forgot what all the wire colors represented. Does anyone know what those other 3 wires are for? The blue one, the black one, and the light green one?
-
Yorb
- Posts: 323
- Joined: Tue Sep 03, 2002 7:29 am
- Car: 1992 Nissan 240SX SE Fastback
- Location: Raleigh, NC
- Contact:
thanks for the pics timeless! =) your amp looks newer than mine did, maybe they changed it in '93? mine was made by Panasonic. hah. anyway, that could be why you couldnt get the harness out.
as for the extra wires... i don't know, but i'd imagine one of them is an amp controller and one of them is for the power antenna (you'll notice that your antenna no longer goes up and down when you turn the car on and off...hmmm. the motor in mine was broken anyway so it just went gnnnrngnrnnrnnrrrrrrr for 30 seconds when i turned the car off, no big loss. start hooking up those wires one by one i guess if you want that feature back). i don't know what the 3rd one is, unless one of those tasks requires 2 wires.
as for the extra wires... i don't know, but i'd imagine one of them is an amp controller and one of them is for the power antenna (you'll notice that your antenna no longer goes up and down when you turn the car on and off...hmmm. the motor in mine was broken anyway so it just went gnnnrngnrnnrnnrrrrrrr for 30 seconds when i turned the car off, no big loss. start hooking up those wires one by one i guess if you want that feature back). i don't know what the 3rd one is, unless one of those tasks requires 2 wires.
-
Timeless240
- Posts: 152
- Joined: Mon Jul 26, 2004 5:12 am
That amp is a Panasonic unit. It's in there pretty secure too, cuz' I couldn't rip it out and I couldn't find any accessible screws holding it to the chassis/panels.
My first thoughts after I cutting ALL of the wires was "Oh $hit, 2 pairs of 4 does not equal 11 wires! Haha!" I feared it was the antenna controls, but upon testing it, my antenna still goes up and down when I switch to FM mode on my HU. I assume it was some kind of control to the amp, maybe some ancient bass/treble control or power/ground leads. It better not be my rear window defogger or something like that.
After riding it for a week, my system has more headroom and the bass definitely goes lower and tighter...even from 4x6s. I guess the amp was acting as a high/low pass filter. I still need a sub, tho, but this will definitely hold me over for a long while now.
One surpise was that there was no SOLID enclosure to those factory rear speakers! Even putting in expensive components in those rear location would hinder their performance. The front locations at least have its own little enclosure and steel door panels to resonate in, but the rears have a half steel/half CARDBOARD makeshift enclosure (as you can see in my first picture.) I defnitely need to tighten those up, sound dampen, and maybe throw in some polyfill. [Would the polyfill help 4x6's at all?] Short of fiberglassing, what would be some other methods to strengthen/reinforce those cheap cardboard panels, and also to preferably make them airtight, too!
I brownbreaded (dynamat) my doors and my trunk area and still have some left, but not enough for all of my interior. I think I'll dampen directly over the rear wheel wells and put a few strips on the cardboard.
My first thoughts after I cutting ALL of the wires was "Oh $hit, 2 pairs of 4 does not equal 11 wires! Haha!" I feared it was the antenna controls, but upon testing it, my antenna still goes up and down when I switch to FM mode on my HU. I assume it was some kind of control to the amp, maybe some ancient bass/treble control or power/ground leads. It better not be my rear window defogger or something like that.
After riding it for a week, my system has more headroom and the bass definitely goes lower and tighter...even from 4x6s. I guess the amp was acting as a high/low pass filter. I still need a sub, tho, but this will definitely hold me over for a long while now.
One surpise was that there was no SOLID enclosure to those factory rear speakers! Even putting in expensive components in those rear location would hinder their performance. The front locations at least have its own little enclosure and steel door panels to resonate in, but the rears have a half steel/half CARDBOARD makeshift enclosure (as you can see in my first picture.) I defnitely need to tighten those up, sound dampen, and maybe throw in some polyfill. [Would the polyfill help 4x6's at all?] Short of fiberglassing, what would be some other methods to strengthen/reinforce those cheap cardboard panels, and also to preferably make them airtight, too!
I brownbreaded (dynamat) my doors and my trunk area and still have some left, but not enough for all of my interior. I think I'll dampen directly over the rear wheel wells and put a few strips on the cardboard.
-
askpcguy909
- Posts: 11
- Joined: Sun Aug 24, 2003 10:07 am
-
Timeless240
- Posts: 152
- Joined: Mon Jul 26, 2004 5:12 am
-
ArticDragon192
- Posts: 2767
- Joined: Fri Sep 10, 2004 5:35 pm
- Car: 91 Z32 2+2
-
vancouverbc
- Posts: 3197
- Joined: Thu Oct 30, 2003 1:30 am
- Car: 1991 240sx
-
vancouverbc
- Posts: 3197
- Joined: Thu Oct 30, 2003 1:30 am
- Car: 1991 240sx
"the motor in mine was broken anyway so it just went gnnnrngnrnnrnnrrrrrrr for 30 seconds when i turned the car off,"
you probably just need a new mast/cord. the plastic cord invariably breaks. it is like a plastic chain that the motor wraps to operate antenna up and down. they say the mast is cheap eg 40 bucks?
you probably just need a new mast/cord. the plastic cord invariably breaks. it is like a plastic chain that the motor wraps to operate antenna up and down. they say the mast is cheap eg 40 bucks?
Re: Successful S13 rear factory amp bypass (Yorb)
Do you think if I had HiFi buys install it, they will know what to do to bypass the stock amp without me telling them? I dont have enough electrical experience to attempt installing my own speakers + head unit...
Re: Successful S13 rear factory amp bypass (Yorb)
Can anyone confirm these exact wire colors with a base model?
Re: Successful S13 rear factory amp bypass (Yorb)
I dont have one! I looked in that exact spot, and I dont have one. Is it possible that its in a different spot for maybe a 89-90? Or is it just for a DOHC SE? Or if the previous owner removed it, I dont see any other wires dangling or anything
-
JTinJacksonvilleNC
- Posts: 90
- Joined: Sat Feb 19, 2005 4:57 pm
- Car: A black 1989 Nissan 240SX coupe.
Re: (askpcguy909)
what's the going rate for a copy?
Re: Successful S13 rear factory amp bypass (Neejay)
the "active speaker system" was an option. so whoever purchased your model from the dealer just opted not to have the powered system i.e. no amps and power was supplied by the head unit. in the event of a powered factory system, normally the head unit puts out now power, only audio signal over + - wires as well as a single wire to the amps telling them when to turn on or off (ignition) if you want to install an aftermarket head unit however and want to use the factory amps then simply couple these three wires: the factory power antenna+wiring harness power antenna+amp turn on wire. for a color coded guide to the wires as well as a detailed install guie for the 240 as well as most other makes and models take a look at http://www.installdr.com1989-1994: http://installdr.com/InstallDo...5.pdf1995-1998: http://installdr.com/InstallDo...1.pdfNeejay wrote:I dont have one! I looked in that exact spot, and I dont have one. Is it possible that its in a different spot for maybe a 89-90? Or is it just for a DOHC SE? Or if the previous owner removed it, I dont see any other wires dangling or anything
Re: Successful S13 rear factory amp bypass (imjustg)
http://carfiche.com/manz/In there you will find decent wiring diagrams.Another note about the factory "Premium Sound" (non-Bose) amps: all inputs have 4 Ohm resistor arrays in parallel (to simulate a speaker load). I took these out when I replaced my stock 240SX head unit with one from an Altima. The Altima unit had a lower output so removing these load resistors increased the volume of the system. Also, all these stock amps have limiters and will not drive any speaker hard no matter what you do to the input side.
-
Felipe
- Posts: 2610
- Joined: Sun Jul 03, 2005 8:37 pm
- Car: abcdefghijklm nopqrstuvwxyz `1234567890-= ~!@#$%^&*()_+
Re: Successful S13 rear factory amp bypass (taxciter)
RUNS out the door to go do it... (stops) Wait, will this work if i have the factory nissan cd unit?
-
Yorb
- Posts: 323
- Joined: Tue Sep 03, 2002 7:29 am
- Car: 1992 Nissan 240SX SE Fastback
- Location: Raleigh, NC
- Contact:
yeah, if your front speaker grilles dont say "ACTIVE" then you almost certainly don't have a rear amp. as that how-to manual that imjustg linked to says.
what that manual doesn't mention is that the factory active speaker system amps in these cars sucks, so while bypassing the amps after you replace the head unit isn't necessary, it's pretty silly not to.
for me, i have a mosfet 50x4 head unit, and some decent infinity kappa midrange and tweets in the front and rear, so taking the 'active' amps out of the flow was an improvement. it may not be an improvement at all if you have the same factory head unit that came in the car.
so basically what i glean from all of this is that if you have ACTIVE on your front speaker grills and you have an aftermarket head unit, bypass the amps. otherwise DON'T, because your stock ACTIVE speaker system head unit won't be able to drive the speakers without the amps.
what that manual doesn't mention is that the factory active speaker system amps in these cars sucks, so while bypassing the amps after you replace the head unit isn't necessary, it's pretty silly not to.
for me, i have a mosfet 50x4 head unit, and some decent infinity kappa midrange and tweets in the front and rear, so taking the 'active' amps out of the flow was an improvement. it may not be an improvement at all if you have the same factory head unit that came in the car.
so basically what i glean from all of this is that if you have ACTIVE on your front speaker grills and you have an aftermarket head unit, bypass the amps. otherwise DON'T, because your stock ACTIVE speaker system head unit won't be able to drive the speakers without the amps.
Re: Successful S13 rear factory amp bypass (Yorb)
hey. does this work for any early model nissans? iv got a 93 max that i gotta bypass the rear speakers. im just wondering if its the same things. thanks.
-
wrightme43
- Posts: 46
- Joined: Sat May 23, 2009 1:29 am
- Car: 1991 240SX SE, 5sp, Super Black
Re: Successful S13 rear factory amp bypass (GXEmax93)
Confirmed fix1991 Nissan 240sx SE with factory active speaker system.
Symptoms. Random RRRAAAGGGGGGHHHBBBBUUUUZZZZZZZZZZZZ from the rear speakers, cycle power and sometimes it would continue and sometimes it would go back to normal sound.
Followed instructions above. System sounds much better, and no more horrible noises.
Sony Headunit, Sony speakers.
Confirmed Fix.
Symptoms. Random RRRAAAGGGGGGHHHBBBBUUUUZZZZZZZZZZZZ from the rear speakers, cycle power and sometimes it would continue and sometimes it would go back to normal sound.
Followed instructions above. System sounds much better, and no more horrible noises.
Sony Headunit, Sony speakers.
Confirmed Fix.
-
Nashville91s13
- Posts: 156
- Joined: Sun Oct 18, 2009 3:13 pm
- Car: 91' s13 240sx hatch
- Contact:
Re: Successful S13 rear factory amp bypass (wrightme43)
I'm going to do this bypass this week because I just installed a JVC Arsenal head unit with Pioneer and Infinity speakers. Wonder if the colors for this DIY would match up with a 95' Pathfinder factory amp. My best friend has one with a Sony head unit and Polks all the way around. He wants to bypass his too. Anybody know?
Re: Successful S13 rear factory amp bypass
I know this thread is a little old but i just installed a aftermarket headunit with factory speakers & no sound comes from the speakers.....Is this due to the factory AMP?
-
Nashville91s13
- Posts: 156
- Joined: Sun Oct 18, 2009 3:13 pm
- Car: 91' s13 240sx hatch
- Contact:
Re: Successful S13 rear factory amp bypass
Double check your colors between your jumper harness and your CD player and your fuses. Your factory radio worked fine before you installed the head unit?jdm2191 wrote:I know this thread is a little old but i just installed a aftermarket headunit with factory speakers & no sound comes from the speakers.....Is this due to the factory AMP?
Find Your Forum!