How the hell do you connect a radio with the stock dimmer switch?

[E30Nova]

I want to use my Alpine head unit out of my 88 325is in my 84 325e and I'm not sure which wires go where. The 88 didn't use the stock fader switch and the 325e still is. I don't mind bypassing it if it makes things easier. But here's the wires that I have:

green/red
white/red
purple/white
brown
light blue/brown
yellow/brown

And then coming from the fader switch is a blue wire and a yellow wire.

Head unit is a CDA-9857. I got the wiring diagram from Alpine's site here:

http://vault.alpine-usa.com/products/documents/CDA-9857%20OM.PDF

And I'm using the 84 ETM here:

http://shark.armchair.mb.ca/%7Edave/BMW/e30/e30_84.pdf

Normally I'm good at figuring this stuff out but I'm having a brainfart. Help plzkthx. :)

[kronus]

Bypass the fader, it's probably shit and your head unit has an internal one. Find the internal fader diagram in the ETM. There should be two inputs and four outputs - note the output wire colors and wire those directly to the matching channels of your head unit.

[E30Nova]

Sounds easy, but the head unit is aftermarket, so there's a positive wire and a negative wire for each speaker. So I have 4 wires from the fader switch, but 8 wires from the head unit connector.

[accident]

that's because the front and rear speakers are wired together. just do what everybody else does and run new wire

[u3b3rg33k]

And here I was thinking this thread was about making the HU dim with the dash lights.

Run new wires. Delete old. win money.

[E30Nova]

Yeah I just searched and found a thread where Luke explained it. But I'm too lazy to run new wires so I'm just gonna unsplice the factory wires and hook em up to my head unit.

[StereoInstaller1]

If that is a premium sound car STOP right the fuck there.

Call me in the AM. You can do this car in about half an hour IF you don't fuck it up.

IF you don't have my number, PM me.

Luke

[accident]

definitely not a premium car. 84 325e.

[StereoInstaller1]

Oh duh...I saw "radio out of my 87" and failed to see the facts.

NVM.

[reelizmpro]

Bypass it and use the Alpine's. Not a big deal. I used to have an 85 325e with 4 20w? speakers and no tweeters. You will want to run new wires and get components.

[DaveSmed]

Just run two new ground wires to the front speakers. No need to tear the entire car apart.

[AbsorbantNut]

If that is a premium sound car STOP right the fuck there.

What difference does it make?

[E30Nova]

Nah, I searched last night and someone had a thread basically identical to this and Luke explained how to do it properly. So I just unwrapped the wires about 12" and found the factory splices. Cut those and found which wires were for the rears and which were for the fronts. Now I have a working stereo in the car.

I also swapped out the premium rear speaker shelf from the 88 and put it in the 84. Though the bigger speakers don't fit flush in the holes, so I have to enlarge them a little.

Has anyone tried putting the later model front speakers into an early model? I mean going from the carpet crap to the plastic ones? Will they fit?

[charlescho]

Nah, I searched last night and someone had a thread basically identical to this and Luke explained how to do it properly. So I just unwrapped the wires about 12" and found the factory splices. Cut those and found which wires were for the rears and which were for the fronts. Now I have a working stereo in the car.

I also swapped out the premium rear speaker shelf from the 88 and put it in the 84. Though the bigger speakers don't fit flush in the holes, so I have to enlarge them a little.

Has anyone tried putting the later model front speakers into an early model? I mean going from the carpet crap to the plastic ones? Will they fit?

share us the link :) im curious myself :)

[StereoInstaller1]

I did a bunch ow writeup over on 'tech after a heated battle with someone over there.

What difference does it make?

I just did a deck (Alpine 102 in fact) in a PS '88 325iS. I used the factory amp...let me make this clear: IF you have an otherwise perfectly functioning all stock PS car, feel free to use the amp. It makes it so easy, sounds great, works nice, all that crap.

Likely would sound better bypassed, but on an early PS car, it sounded pretty damn good.

Also, down the road, adding more power is easier if the stock PS wiring is in place and in use.