E30 Stereo Wiring for Dummies

[MaxBell]

Hey everyone;

I've been reading and using the search function on here for a few weeks, but havn't posted yet. However, I've hit some pretty huge walls and so I think it's time to seek help.

My lastest project is I'm trying to wire up a new stereo into my new (old) 1987 325i E30 (Premium Sound, with the fader in the dash and the amp in the trunk) Guess what? IT'S SUPER NOT EASY! I'm wiring in a Alpine CDE-100 headunit, I'm keeping the stock speakers for now. I can't use a wiring harness as they don't exist for that old car.

If anyone knows of a good DIY or wants to start giving me some info, I'd be very glad. I can't handle "Teenage Dream" and the rest of the shitty Top 40 radio listening any more.

This post was one I found, but I am wondering if it would work out for premium sound? (i have the two speakers in the back, amp, fader):

OK, stop right there.

If you have a non premium sound car, you do not need (nor would I recommend) to run new wires...everything you need is already in the dash.

That diagram you made in the OP is WRONG, and will smoke your deck after a while, plus it will sound really shitty.

Ask "Danny" what a difference it made, I did his in 15 minutes while we were at the Picnic.

Here is what to do:
1. Remove deck

2. remove fader

3. unwrap wires to the fader, about 8 to 10 inches before the plug.

You will find 2 sets of 3 wires, all brown, or like brown/orange.
These are your speaker negatives.



Now, use yellow/red for the left front positive and the wire it is twisted with is the ground for that speaker.
Yellow/black will be the left rear positive, the twisted wire is the ground for that speaker.
Blue/red is right front, again with the twisted wire thing...bet you see the pattern now, dont'cha?

Seriously, if this takes you half an hour, I would be amazed.

You will also see how the 2 blue wires feed into the fader, and the chassis ground.

If you see a grey/red wire, that is the dash light circuit. Cap it off, you won't need it.

BTW, the stock 20 year old BMW wire is excellent, use it in good faith.

Cheers.

[graffeedy5]

I used the diy I found on here, but my car only has 4 speaker wires, apparently I'm supposed to have 8 in the dash. I can't locate the amp or the wires that are supposed to be in the trunk.

http://www.unitedbimmer.com/forums/car-audio-electronics/7945-e30-stock-headunit-stereo-aftermarket.html

that tut actually.

[bad_azz_bmr]

Easiest and beat thing to do is scrap all of the original speaker wires, run new wires to the speakers and hook up power, ground, antenna, and ignition.

[graffeedy5]

I can use the existing power, ground, and antenna wires though right?

[StereoInstaller1]

Easiest and beat thing to do is scrap all of the original speaker wires, run new wires to the speakers and hook up power, ground, antenna, and ignition.

Don't be silly, the BMW wire is incredible. It is WAY better than any shit you are gonna wanna pay for, trust me on this.

You can't strip other 20 year old wire and expect it to still be nice and shiny.

[graffeedy5]

Don't be silly, the BMW wire is incredible. It is WAY better than any shit you are gonna wanna pay for, trust me on this.

You can't strip other 20 year old wire and expect it to still be nice and shiny.

anyone know why I only have 4 speaker wires when that DIY said I should have 8?

[StereoInstaller1]

anyone know why I only have 4 speaker wires when that DIY said I should have 8?

What car you got?

[mr.vang]

anyone know why I only have 4 speaker wires when that DIY said I should have 8?

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[StereoInstaller1]

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Premium Sound does not use speaker ground for amplifier input, and if he still has the factory amp and fader, he will have only 2 wires for "speakers" which is why there is so much confusion.

[nando]

Don't be silly, the BMW wire is incredible. It is WAY better than any shit you are gonna wanna pay for, trust me on this.

You can't strip other 20 year old wire and expect it to still be nice and shiny.

werd. I've been using the engine harness from my '88 parts car as a "parts" harness. I had been buying wire at the local hardware store, but the quality is horrible. You can't even solder the stuff because it's all nasty inside.

eventually when I gut the rest of the car, I'll strip all the wire out of it and keep it for future use. maybe even steal the premium sound wiring since I was retarded and cut into mine.. :(

oh yeah, the wires on later BMWs suck. especially the "shrink wrap" stuff on the M50. you can pull it apart with your bare hands, and the insulation on the wires gets all hard and brittle. Nothing like that on the E30 harnesses I've taken apart..

[StereoInstaller1]

Agreed (^).

I have done a few installs on E90s and such, the wire is nothing like E30 wire.

[graffeedy5]

What car you got?

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i stripped the end of each wire though and there's only one type of wire inside. it's an 87 325e. I've got 4 speaker wires, front left, front right, rear left, rear right, where are the positive and negatives? Can anyone take a picture of what it should look like?

[StereoInstaller1]

You need to disconnect the fader and strip the harness back about a foot or so.

You will find twisted pairs: 2 blue sets, 2 yellow sets.

BLACK STRIPE IS POSITIVE!

[graffeedy5]

the speaker wires that were going into the stock headunit are yellow, yellow/brown, blue, blue/brown. I have to strip those back a foot to get to the positive and negative?

[StereoInstaller1]

Yes. You MUST get past the fader wiring.

Brown is ground, don't forget.