Radio Wiring and Amp Bypass

[MrDomino]

I'm another person trying to figure out the hack job done by a previous owner.

1987 325is (Premium sound)

So I took out the gauge cluster (I had to do it for something else anyways) and stripped back the wiring a bit and found nine wires.

1. Brown/Black - Ground?
2. Red/Green - 12V unswitched
3. Gray/Purple - 12V accessory
4. Yellow/Red - Front Left
5. Blue/Red - Front Right
6. Yellow/Black - Rear Left
7. Blue/Black - Rear Right
8. Gray/Red - not sure
9. Brown - Another ground?
10. White - not sure

I've stripped enough back that I'm now behind the gauge cluster so I don't think going further is going to find me these twisted pairs that everyone has.

I then went to the back of the car and checked and the amp is still there. I have the following wires running into it.

1. Black/Purple - LR speaker+
2. Gray/Brown - RF speaker+
3. Gray/White - RF speaker-
4. Black/Brown - RR speaker+
5. Black/White - RR speaker-
6. X
7. Black/Brown - LR speaker-
8. X
9. X
10. Brown - Ground
11. Black/Red - Power input
12. X
13. White - Power input
14. Yellow/Black - Fader Left (from front of car)
15. Yellow/Red - Fader Left (from front of car)
16. Gray/Purple - LF speaker+
17. Gray/Red - LF speaker-
18. Black/Brown - Ground
19. Blue/Black - Fader Right (from front of car)
20. Blue/Red - Fader Right (from front of car)

So where do I go from here? Do I not use any grounds? Do I have to run new lines? I'm not sure where to go since I'm not seeing the twisted pairs.

As added incentive- if I do get this figured out then I'll write up exactly what I did with pictures so that others can benefit from it.

[Quinthirty]

One more thing about my car stereo is that the PO seemed to have set it up in such a way that the radio would power up even if there were no keys. So its like directly connected to the battery of the car. I wanted to change that.

Going back to the four wires above, I referred to the guidelines on page 1, and managed to power up the stereo at position 1, and eliminated the possibility of discharging my battery when parked for a few days / weeks. What I noticed though was that every time I got to position 1, when the power would kick-in, the clock would reset to zero. However, all other settings would be retained.

I went back to the 4 wires, exchanged Red / Green with Purple / Yellow on both power sources indicated in the HU (unswitched & ACC / position 1), and now its back to the former set-up.

Questions:

1. Can I not power the stereo on position 1 only without resetting the clock automatically? If yes, is there something wrong with my stereo that it doesn't retain clock settings?

2. Are E30 stereos really wired this way, that the power source is direct to battery?

3. Should I re-do / revisit the wiring as the PO did a hack job with the install?

[Quinthirty]

Hi, I'm a newbie at this. Just wanted to make sure that I got the wiring right on mine as I got to take out some portions of the dash and wanted to check out the aftermarket wiring. PO put in an aftermarket Blaupunkt but sometimes there's popcorn, and the stereo power automatically shuts off when it reaches a certain volume (like a rev limiter?)

Now for the wiring. There seems to be four wires that are loose. According to the HU's diagram, they are the power sources. These are:

1. Brown
2. Red / Green
3. Green / White
4. Purple / Yellow

Just trying to match it with the inputs on the 1st page, and I think I got the 1st two right. I'm unsure of the last two wirings as my model is different. For all intents and purposes, its an '88 coupe & does not have premium sound.

Thanks R3v. Luke, you rock!

[StereoInstaller1]

All of the wires where behind the radio. Didn't have to run anything. The grounds were not spliced off of the fade switch. They were spliced off of the radio wires. Very simple once I realized that. I was so concentrated on the fader that I over looked the rest of the wires.

Yellow/red+ driver front
Yellow/brown - driver front
Yellow/black+ driver rear
Yellow/brown - driver rear
Blue/black + pass rear
Blue/brown- pass rear
Blue/red+ pass front
Blue/brown- pass front

Yes, sounds like you found them

[Vdubmt]

Could be but in my case, the twisted pairs did not come off of the fader. Instead they came off of the wires that were connected directly to the rear of the radio. Once I realized that I tested the wires to see what ground went to what speaker. Very simple.

I think most people just don't peel back far enough to see the twisted pairs. Once you find the pairs it is pretty evident which are the grounds.

[CB-M3]

I think most people just don't peel back far enough to see the twisted pairs. Once you find the pairs it is pretty evident which are the grounds.

[Vdubmt]

All of the wires where behind the radio. Didn't have to run anything. The grounds were not spliced off of the fade switch. They were spliced off of the radio wires. Very simple once I realized that. I was so concentrated on the fader that I over looked the rest of the wires.

Yellow/red+ driver front
Yellow/brown - driver front
Yellow/black+ driver rear
Yellow/brown - driver rear
Blue/black + pass rear
Blue/brown- pass rear
Blue/red+ pass front
Blue/brown- pass front

[StereoInstaller1]

I have to the point that yellow and blue go to the back of the radio and the remaining 4 go behind the cluster. I do not have premium system. It seems that it should be a no brainer

Yours sounds like running new wires might be easier for you.

I have seen some that the ground junctions for the front and rear are under the drivers seat...so running extra wire to that point would be dumb, as it would be just as hard as a full re-wire.

[Vdubmt]

I figured it out. Was very is simple. I tested the negative wires to see which one went to what speaker. I was having a brain freeze there for a minute. Once I pulled the speakers and seen what wires went where the rest all fell into place. Thanks for the help and for this awesome thread.

[Vdubmt]

Would these be the splices.. Neither of them come off of the fader wires. They both connect to the wires that go directly to the back of the radio. The blue on also doesn't seem like it's two wires in. Looks like one wire that the other wire is spliced into

[Vdubmt]

I have to the point that yellow and blue go to the back of the radio and the remaining 4 go behind the cluster. I do not have premium system. It seems that it should be a no brainer

[StereoInstaller1]

It seems that everything that I find says that the fader will have 8 wires with a splice about a foot back. I've been searching through the thread looking for something similar but no luck yet. Still looking. Installing a Kenwood kdc-200u. Thanks.

How far have you unwrapped the harness? Have you unwrapped enough that the fader wiring fell out of the harness? typically, another foot or so past the yellow and blue looping back to the radio side is enough.

[Vdubmt]

It seems that everything that I find says that the fader will have 8 wires with a splice about a foot back. I've been searching through the thread looking for something similar but no luck yet. Still looking. Installing a Kenwood kdc-200u. Thanks.

[archie]

Luke RULES!
Thanks for your help the other day.

A

[StereoInstaller1]

Why do you think this car is special? You have an early, non-amplified "standard" system with the fader in dash. Somwhere in this thread you will find several others posting the same setup and how to fix it.

What exactly are you installing?

Luke