91 300D Stereo Upgrade..What do I have from factory? - PeachParts Mercedes-Benz Forum

JamesDean · #1 11-04-2012, 12:01 PM

Hey everyone,

A while back I bought a Kenwood head unit to put in my 300D, I finally am getting around to it and I'm trying to figure out what setup I have in the car now. Its stock but I was looking through the FSM and theres a bunch of different ones.

Here is what I know:

-I've got a MB labeled CD player, not tape.
-I dont have a CD changer.
-Only my front dash speakers work, the fader has no effect.
-I believe I've got some kind of amplifier mounted on the right side of the trunk behind the lining.

I THINK these are the relevant pages from the FSM:

anziani · #2 11-04-2012, 12:10 PM

You might have better luck if you post this in the "Car Audio and Multimedia" forum.
Anziani

mbdoc · #3 11-05-2012, 08:19 AM

MB didn't have an in-dash CD unit until 2000.

JamesDean · #4 11-05-2012, 11:42 AM

Quote:

Originally Posted by mbdoc

MB didn't have an in-dash CD unit until 2000.

You sure? My first post has a snip from the FSM, they called it "Two Piece Radio with CD Player" Not sure if that meant CD in trunk or dash though.

JamesDean · #5 11-05-2012, 08:31 AM

That might explain why it really doesnt work all that well. I burnt some audiobooks on to CD-R's and it just said ERROR at me.

Here's what it looks like:

jcyuhn · #6 11-05-2012, 10:19 AM

That is definately not the radio that came in the car. That said, I don't recognize that radio. It looks much like the 210 head unit, but I have never seen a 210 with an in-dash CD, only a tape player.

Most likely your car came with the infamous Becker 1432 two-piece radio and aktive Bazz system. I did a rip-and-replace of the 1432 in my old '93. I found the easiest approach was to start from scratch, so although I retained the OEM speakers and active bass system, I ran all new wiring. You also need an antenna extension, as the 1432 tuner is in the trunk rather than the head unit. There's some discussion of my travails in the archives, lemme see if I can find them...

This is a bit rambling and has some Becker 1492 stuff, but may be helpful: http://www.peachparts.com/shopforum/car-audio-multimedia/208617-94-e320-w124-aftermarket-head-unit-upgrade.html

And... http://www.peachparts.com/shopforum/car-audio-multimedia/207863-1432-dead-what-replace.html

Good Luck.

JamesDean · #7 11-05-2012, 11:41 AM

Quote:

Originally Posted by jcyuhn

That is definately not the radio that came in the car. That said, I don't recognize that radio. It looks much like the 210 head unit, but I have never seen a 210 with an in-dash CD, only a tape player.

Most likely your car came with the infamous Becker 1432 two-piece radio and aktive Bazz system. I did a rip-and-replace of the 1432 in my old '93. I found the easiest approach was to start from scratch, so although I retained the OEM speakers and active bass system, I ran all new wiring. You also need an antenna extension, as the 1432 tuner is in the trunk rather than the head unit. There's some discussion of my travails in the archives, lemme see if I can find them...

This is a bit rambling and has some Becker 1492 stuff, but may be helpful: http://www.peachparts.com/shopforum/car-audio-multimedia/208617-94-e320-w124-aftermarket-head-unit-upgrade.html

And... http://www.peachparts.com/shopforum/car-audio-multimedia/207863-1432-dead-what-replace.html

Good Luck.

Hmmm. There is a CD player option in the FSM though..

Here is what I would like to do:
Keep the factory amp and active bass system and wire it into my Kenwood. Can I just interface the line out of the kenwood with the factory amp/bass system? Or is there more to be done?

jcyuhn · #8 11-05-2012, 11:51 AM

Quote:

Originally Posted by JamesDean

Hmmm. There is a CD player option in the FSM though..

Here is what I would like to do:
Keep the factory amp and active bass system and wire it into my Kenwood. Can I just interface the line out of the kenwood with the factory amp/bass system? Or is there more to be done?

You can retain the active bass amp, but it uses speaker level inputs, not pre-amp level inputs. I did it on my '93 and it worked surprisingly well. Since your Kenwood probably has a 4 channel amp, you are best off wiring the head unit directly to all four speakers. The factory system uses a 2 channel amp through the fader in the center console. You can retain this, but you give up half the power of the head unit. Don't forget to run the turn on signal to the amp.

JamesDean · #9 11-05-2012, 11:56 AM

Quote:

Originally Posted by jcyuhn

You can retain the active bass amp, but it uses speaker level inputs, not pre-amp level inputs. I did it on my '93 and it worked surprisingly well. Since your Kenwood probably has a 4 channel amp, you are best off wiring the head unit directly to all four speakers. The factory system uses a 2 channel amp through the fader in the center console. You can retain this, but you give up half the power of the head unit. Don't forget to run the turn on signal to the amp.

Interesting.

In my 420SEL I was able to access all 4 speakers from the amps mounted behind the top of the back seat. Is there a similar location for the 124s?

I could buy a decent 4 channel amp and install it in the trunk, wire up the speakers and parallel off into the active bass unit.

Or I could run 4 sets of wires to where-ever and tie into the active bass unit.

JamesDean · #10 11-05-2012, 06:15 PM

I believe this unit IS actually original to the car. I recall looking at the car and finding the CODE document thing in the manual booklet thing. I'll have to find where I put it and everything.

If the Active Bass systems run off of speaker level inputs, its likely that it runs off the rear speaker lines. Since my rear speakers aren't working, theres nothing to kick the active bass system on.. Perhaps the fader has died somehow.

In other MB's the amplifiers serviced one half of the vehicle (front/rear left or front/rear right) I don't believe BOTH rear halves would be out. It must be a signal problem upstream. Perhaps at the do-nothing fader. Maybe it crapped out and someone bypassed it ****tily.

JamesDean · #11 11-06-2012, 10:30 PM

Is this guy the Active Bass amplifier?

If so, where are the normal other speaker amplifiers?

jcyuhn · #12 11-07-2012, 11:04 AM

Quote:

Originally Posted by JamesDean

Is this guy the Active Bass amplifier?

If so, where are the normal other speaker amplifiers?

Yes, that is the AB amplifier. The tuner/amp for the 1432 is supposed to be in that other clip behind the AB amp. Can't quite tell from the picture what is currently residing there.

rob m · #13 11-07-2012, 10:32 PM

My 91 300e had two smaller silver amps where your larger black one is the thing behind it is the tuner and preamplifier. The deck up front mine was cassette. Is just a controller. Think of the dash part and the trunk part as being your deck in two pieces. You still should be able to install a new deck. Run new wires to the dash speakers the wires for the rears can then be grabbed at the center console fader and the door speakers will be at the amp in the trunk. Save yourself a headache and install a small amp in the trunk where the factory controller is to run the doors. Run them as mid bass speakers.. You have to run an antenna cable from the antenna to the dash so run the power and preamplifier cables for the amp at the same time go out to the battery behind the glove box

JamesDean · #14 11-08-2012, 11:09 PM

Alrighty,

So I unintentionally dug into this project tonight and I found out. That the deck in fact was not original to the car. I took out the deck and the antenna wire was just cut and hanging out.

There was two speaker couplers just hanging there, disconnected. Testing them revealed they were connected to rear speakers. They seemed to pass through the fader as it had influence on them but not the fronts.

There was a thick white cable disconnected as well. Presumably this connected to the Tuner/Amp unit in the trunk.

After battery testing all four of the speaker couplers and getting a response from each speaker (except the doors) I decided to go-ahead with installing my new Kenwood deck. I attached the deck's speaker outputs to the ones in the console and fired it up.

It worked. I cranked up the music, nothing from the active bass speakers. I kept climbing in volume and then the deck cut out and something in the trunk clicked.

Originally I had thought the previous owner had ran or somehow directly accessed each speaker because with the battery test each buzzed.

But now I think that the factory amp/tuner module is still in tact.

So tomorrow, the plan is to remove the tuner/amp module and patch my Kenwood directly to the speakers as best as I can. Then see if I can figure out a way to patch the active bass amplifier into the system as well. If I understand how it works, it should be as simple as coupling the active bass to the rear speaker line and powering up the active bass amp..There was two wires in the center console I could not account for though. One I believe was for illumination and the other was unknown. It might have been for "antenna control" which also powers up the active bass amp.

Ultimately, perhaps next year, I'll drop in a normal 50x4 amplifier and run that instead of the head unit. I might also replace the speakers depending on how I feel about them. But for now, my main listening is audio books and this should suffice.

JamesDean · #15 11-09-2012, 01:21 PM

Here's my plan:

Changes to Active Bass wiring: