Radio Wiring and Amp Bypass

[bobdavisnpf]

bpiersma, sounds like you're fairly close to getting at the stereo wiring harness. If you can pull up the driver's side carpet outside edge, you can inspect for damage. You can pull the rear side panels to see the rear speaker wiring as well.

[Flexx]

I used this and it worked out well.

I own a 89 325is with premium sounds, amp and no external fader and was wondering if that was all you did?

I have the same set up but my sounds good at start up but 2
Mins in the sounds starts to fade.

I have 4 sets of speaker wires, no orange/brown wires but the positive and negative wires wrapped both for front and back speaker wires to
Make it easy.

Did you follow the write up?

[cspec]

Did this diagram work for you? I have an early build 1990 with premium sound and no external fader.



Thanks!

Edit: This worked well for me!

[bpiersma]

Forgot to add:

There is no in-dash fader.

[bpiersma]

Yeah, that works...not ideal, but it works. There are so many different setups in these cars its crazy, glad you got through it!

Luke

Luke, I have what I think is a somewhat unique issue. I purchased this 1991 318i convertible with a crappy aftermarket HU already installed (OEM speakers and trunk amp). Thankfully the original HU was in the trunk in a box. I've now reinstalled that, double checked all the wires, but am getting no sound whatsoever to the speakers. Antenna powers up, HU powers up, but no sound. It doesn't look like the previous owner did anything to the amp (original wires and connectors). Yes, there is power to the amp (12V). I think I have premium as there are tweeters in the doors. My objective is to use the original HU and speakers (go back to stock). Does it make sense to bypass the amp and use the original HU?

Other facts that may be interesting: I have all the seats removed along with various other components of the car (center console, taillights). I cannot imagine that affecting the speakers, but maybe I'm missing something.

Any thoughts or ideas? Thanks in advance!

[Rontgen]

Thanks!

[gath]

Did this diagram work for you? I have an early build 1990 with premium sound and no external fader.

Thanks!

I used this and it worked out well.

[Rontgen]

I want to do a factory amp bypass on a late ‘89 with premium sound with no fader. Is thing a good diagram to use?

Did this diagram work for you? I have an early build 1990 with premium sound and no external fader.

Thanks!

[gath]

All done! got it figured out.

[parkerbink]

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10" Lukebox with Sundown audio SD2 10" and Rocford Fosgate Power 1000 Amp

[ThatM20Guy]

Took another crack at trying to figure out the wiring on my headunit and am honestly stumped. I only have the one white wire coming out of the dash (the one on my finger) which I assume would go to the remote on the headunit side.

If correct then this is the only wire I have left to connect and it should get rid of the miswire code.

[VWguyBruce]

Another successful amp/fader bypass on my late model coupe. Many thanks to the OP and everyone else that assisted in making this thread what it is.

Now to hunt down the bad driver in the rear....

[bobaflesh]

Hey bobaflesh, I just went through this exact scenario a few days ago in a '90 with premium sound. It was a bit tedious but I got it right on the first try including the factory amp bypass. If you still need help with this, pm me, and I can walk you through it step by step on the phone tomorrow (Sunday) afternoon.

Hey thank you so much! I will go ahead and try to bypass the amp per the sticky when I have some time. Will let you know.

[KrautnotRice]

Hey bobaflesh, I just went through this exact scenario a few days ago in a '90 with premium sound. It was a bit tedious but I got it right on the first try including the factory amp bypass. If you still need help with this, pm me, and I can walk you through it step by step on the phone tomorrow (Sunday) afternoon.

[bobaflesh]

I am having problems installing a Pioneer head into a 1990 325i sedan.. Got the premium sound system (tweeters on doors and rear deck speakers) and followed the stickied guide, but have no sound.

I have attached two photos so maybe someone could shed some light on the issue for me. Thank you!