Radio Wiring and Amp Bypass

[6670charger]

After going back, is this the info? Just use the Dash wire to speaker wire part? Also, I didn't have twisted pairs; only positives. I assume that will hold true in the trunk as well. Do I connect both speaker wires to the single positive wire, or no? As I said once before, I understand the absolute basics of electrical wiring, and I'm extremely new to stereo wiring. Some of the simplest of things to others are baffling to me until I work with it a bit. Right now, my assumption is that since all the factory wiring already goes where it's supposed to, this should just be a matter of disconnecting the amp, and then connecting whatever wires go from the amp to the speakers to the correct wire coming from the deck to the amp. I also assume that the amp in the deck will power everything just fine, and that the factory amp combined with the amp in the deck is either putting out too much power, too little power, or interferes with the deck amp in some way which is what is causing the spitting in my speakers at higher volume. Since I already have the deck connected correctly, now it's just a matter of determining which wires from the amp go to which speakers.

Dash Wires-----------Speaker Wires

RF+ Blue/Red-------------Grey/White
RF- Brown/Orange--------Grey/Brown

LF+ Yellow/Red------------Grey/Red
LF- Brown/Orange--------Grey/Violet

RR+ Blue/Black------------Black/White
RR- Brown/Orange--------Black/Brown

LR+ Yellow/Black----------Black/Red
LR- Brown/Orange--------Black/Violet

[6670charger]

Checked the wiring diagrams in the manual I downloaded from wedophones.com. I doesn't really tell me much. The diagram that shows the premium sound system with the amp doesn't show any wiring for the speakers from the amp. The other diagram without the premium system shows the speakers, but only as they're wired from the fader. What I need is the wiring from the amp to the speakers. I think I found that as posted in my previous reply. I hope this is correct, but, I'm still not certain what I'll find with regard to wiring back there since my deck is only connected with positive wires. Do the speakers connect to those wires using the positives only also?

[6670charger]

Any thoughts on where the factory amp might be on an 88 vert? Took out the left side trunk panel and didn't find anything anywhere near the power antenna. I know I have one as I have tweeters in the doors and a white amp wire that I had to connect behind the deck in order to get sound. Did I not look far enough back? Didn't find anything on the other side of the trunk either.

[6670charger]

OK, found the amp. It was behind the upper trunk liner and below the convertible top boot. Only has one plug for it, and I'm pretty sure I found the positive speaker wires: RF-grey/white, LF-grey/red, RR-black/white, and LR-black/red. Again, 88 325i vert.

I assume that since there is only one plug, both the input wires from the deck and the output wires to the speakers are all in the one plug, and that my next step is to cut off the plug, and connect the positive speaker wires I just identified to the correct colored wires coming from the deck? I have all of the wires as identified below, to include what appear to be the speaker negatives:

Dash Wires-----------Speaker Wires

RF+ Blue/Red-------------Grey/White
RF- Brown/Orange--------Grey/Brown

LF+ Yellow/Red------------Grey/Red
LF- Brown/Orange--------Grey/Violet

RR+ Blue/Black------------Black/White
RR- Brown/Orange--------Black/Brown

LR+ Yellow/Black----------Black/Red
LR- Brown/Orange--------Black/Violet

Looks like BlueBMW had something similar in his car on page 13. I don't intend to run new wire to the front speakers like he did, nor do I get how to re-purpose the wiring in the rear. I understand the concept, but have no clue how to actually do it. This is the first system where I've had to do anything more than just connect the deck to the wires in the dash.

Since I seem to have speaker ground wires, do I use the negative wires too, or just the positives? What confuses me is that I don't have ground wires from the dash to the amp, but apparently do from the amp to the speakers.

[6670charger]

This is what I have for wiring in the trunk. There are no twisted pairs, just all of the colored wires that were mentioned in other parts of this thread going way up into the convertible boot area. Again, it seems that I have ground wires for each of the speakers, yet, I'm only connected to positive wires at the deck. What do I do with the ground wires? Are they used? If so, where/how? If they're not, then it sounds like all I need to do is connect all of the relevant positive wires together and I should be fine. I'd try this on my own, but, if it doesn't work, then I either have to re-connect everything they way it was again, or live without any stereo at all for however many days it takes for someone to help me out with this. Just need to know about the grounds and how/if they come into play at the amp.

[dogsbark26]

I am no expert. It is my understanding that all electrical components require a circuit. That is, both a positive and a ground. I believe that speakers all require both a positive and a ground. Speakers will not work with only one conductor attached.

I have never understood that portion of this thread discussing the low-voltage "signal" wires containing just one conductor. I get it that the signal is actually carried on just one of the conductors (unless you are using a "balanced" output/input - but that is in specialized equipment). But that does not apply here.

So I guess this response is not going to help you. Sorry.

[6670charger]

I am no expert. It is my understanding that all electrical components require a circuit. That is, both a positive and a ground. I believe that speakers all require both a positive and a ground. Speakers will not work with only one conductor attached.

That's my problem. I understand electrical the same way. It seems to me that the speakers must ground in some way since there seem to be wires for it, but not sure how it works with only the positive wires connected at the deck. :loco:

[StereoInstaller1]

That's my problem. I understand electrical the same way. It seems to me that the speakers must ground in some way since there seem to be wires for it, but not sure how it works with only the positive wires connected at the deck. :loco:

AH HA! I finally figured out why this is kicking your ass so bad!

Pay attention here: Those wires coming from the deck are AMPLIFIER INPUT wires, NOT speaker wires...get it? Speaker wires run speakers, the wires in your dash do not, they do not connect to the speakers at all.

That is why this is kicking your ass, you are confused because they look just like speaker wires.

Those 4 positives and 1 ground are INPUT WIRES, the one negative for all 4.

Oh, and every bit of info is in the ETM, if you can't find them, you need to work on your diagram skills.

All of them are shown in clear detail, look for "HiFi Amplifier" in the ETM.

So, that being said, I need the stress this: The deck feeds the audio to the amp, the amp runs the speakers. That is why there is only 1 input ground, later E30s are wires differently. There is still only 1 input ground though.

That is why I keep telling you to read the entire "bypass" thread, the info of what to do about you having 5 wires from front to back is there.

Yet another point: Speakers do not get "ground", they get a negative signal from whatever runs them. Oh, and please start using "negative" instead of "ground" unless chassis ground is actually present on the wire. It helps clarify your questions. When I used the word "ground", I am referring to chassis ground, even when referring to the amp's negative input.

Luke

[StereoInstaller1]

BTW, if you have a "5 wire" harness, you MUST run new wires to at least two of the speakers. Typically, the front are the easiest to run wires to. You can use the 4 positive input wires to run the rear speaker at the amp, we call this "re-purposing" the wires.

[6670charger]

Ok. Was hoping to not have to do all that due my limited time, but sounds like I have no choice. Based on what I've read so far, it looks like if I do what BlueBMW did I should be good.

Since he had what I have (4 wires with no twisted pairs), it seems that his setup is what I need to do:

Deck Connections:
Car ---> Deck
Red/Green ---> Yellow (12V Const)
Violet/White ---> Red (12V ACC)
Brown/Black x2 ---> Black (Ground)
Gray/Red ---> Orange (Illumination)
White ---> Blue (Antenna On)
White ---> Blue/White (Amp On)

Left Rear Speaker:
(+) Radio: Yellow/Red ===> Amp: Black/Red
(-) Radio: Yellow/Black ===> Amp: Black/Violet

Right Rear Speaker:
(+) Radio: Blue/Red ===> Amp: Black/White
(-) Radio: Blue/Black ===> Amp: Black/Brown

Speaker Connections:
L/F + R/F speakers: New Wire directly from deck to speakers

L/R:
Speaker + ---> Black/Red ---> Yellow/Red ---> Green (L/R +)
Speaker - ---> Black/Violet ---> Yellow/Black ---> Green/Black (L/R -)

R/R:
Speaker + ---> Black/White ---> Blue/Red ---> Violet (R/R +)
Speaker - ---> Black/Brown ---> Blue/Black ---> Violet/Black (R/R -)

If I understand this all correctly, basically, all the wires I have connected to the deck's speaker wires right now will become the pos/neg rear speaker wires, and I run new ones to the fronts. Assuming that this is correct, my only other question involves the door tweeters. Do these simply go away, do I run a pos/neg from the front speaker stereo wires to both the footwell speakers AND the tweeters, or do they get powered somehow through all the magic involved in the new connections in the trunk? I've seen a lot of reference to them with regard to determining what type of system people have, but nothing so far with regard to powering them once the bypass is done; only re-wiring the kickpanel speakers. Maybe I missed something?

[StereoInstaller1]

Ok. Was hoping to not have to do all that due my limited time, but sounds like I have no choice. Based on what I've read so far, it looks like if I do what BlueBMW did I should be good.

Since he had what I have (4 wires with no twisted pairs), it seems that his setup is what I need to do:

Deck Connections:
Car ---> Deck
Red/Green ---> Yellow (12V Const)
Violet/White ---> Red (12V ACC)
Brown/Black x2 ---> Black (Ground)
Gray/Red ---> Orange (Illumination)
White ---> Blue (Antenna On)
White ---> Blue/White (Amp On)

Left Rear Speaker:
(+) Radio: Yellow/Red ===> Amp: Black/Red
(-) Radio: Yellow/Black ===> Amp: Black/Violet

Right Rear Speaker:
(+) Radio: Blue/Red ===> Amp: Black/White
(-) Radio: Blue/Black ===> Amp: Black/Brown

Speaker Connections:
L/F + R/F speakers: New Wire directly from deck to speakers

L/R:
Speaker + ---> Black/Red ---> Yellow/Red ---> Green (L/R +)
Speaker - ---> Black/Violet ---> Yellow/Black ---> Green/Black (L/R -)

R/R:
Speaker + ---> Black/White ---> Blue/Red ---> Violet (R/R +)
Speaker - ---> Black/Brown ---> Blue/Black ---> Violet/Black (R/R -)

If I understand this all correctly, basically, all the wires I have connected to the deck's speaker wires right now will become the pos/neg rear speaker wires, and I run new ones to the fronts. Assuming that this is correct, my only other question involves the door tweeters. Do these simply go away, do I run a pos/neg from the front speaker stereo wires to both the footwell speakers AND the tweeters, or do they get powered somehow through all the magic involved in the new connections in the trunk? I've seen a lot of reference to them with regard to determining what type of system people have, but nothing so far with regard to powering them once the bypass is done; only re-wiring the kickpanel speakers. Maybe I missed something?

Actually, you are getting it, hooray!

You do have to run new front speaker wires and there is an easy way to do it: simply cut and connect the wire going to the front speakers under the rear seat. Very easy to "return to stock" so it is easier to add an amp, too.

Run 2 pair of wires from your deck to under the rear seat. Normal 18ga is fine, no tiny crap, but your normal speaker wire. You will need like 25 feet total. Pull the panels under the left side of the dash, pull the door sill trim strip, pull the bottom of the rear seat.

Run your two pairs out the back of the deck hole, through the dash to the left front corner of the dash, at the firewall, then straight down and right in conjunction with the factory harnesses. You don't even have to remove the left kick panel if you are careful and just follow the factory routes. I like to wrap the wires in tape every few inches so they stay tidy.

Pay careful attention as you route past the steering column; a shitty job of this can kill you.

If you have this tool:

available at Sears and lots of auto parts stores including NAPA, it is a 20 minute job total, including connecting the wires.

Make sure you are not running through the clutch or brake pedal linkage, look at what you are doing, not responsible, etc.

Does the diagram in the ETM makes sense yet? That shit takes a while to sink in, especially if you have only a little experience. It is just a whole new roadmap, but all of the answers are there.

Luke

[6670charger]

simply cut and connect the wire going to the front speakers under the rear seat.

Great! Sounds like I have a plan I can use. I like your idea of running the new wires to existing which would eliminate having to tear apart so much of the car to get to things. The one thing that confuses me a little is your reference above to "the wire" going to the front speakers. I assume you're referring to this as a plural reference to the front speaker wires? I have LF: gray/red (+), gray/violet (-); and RF: gray/white (+), gray/brown (-), based on your initial post.

[StereoInstaller1]

Great! Sounds like I have a plan I can use. I like your idea of running the new wires to existing which would eliminate having to tear apart so much of the car to get to things. The one thing that confuses me a little is your reference above to "the wire" going to the front speakers. I assume you're referring to this as a plural reference to the front speaker wires? I have LF: gray/red (+), gray/violet (-); and RF: gray/white (+), gray/brown (-), based on your initial post.

Yes, exactly...now go get it the fuck DONE!

[6670charger]

Alrighty then!!!

Back speakers connected and working fine. Great sound at all volumes and EQ settings. Now to connect up the fronts.

[6670charger]

OK, now trouble. I've run two pairs of wires from the deck through the dash and along to the spot under the back seat where I found all the correct color wires for the speakers. I connected all the new wires to the corresponding speaker wires based on a flow chart I made for them, and I get no sound out of the fronts at all. I connected into the speaker wires that appear to lead back to the front of the car, so I assume they're the ones that ultimately connect to the front speakers.

Any thoughts?