Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Car Audio and Multimedia

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 01-23-2008, 06:44 PM
Registered User
 
Join Date: May 2005
Location: Northern VA
Posts: 225
Any 123 Radio Wiring Expertise?

Purchased a Sony XPOD 410U CD receiver to replace the existing Kenwood KRC-860 cassette receiver in my '83 300D. Looks like the PO got the Kenwood for hookup into the car phone. For some reason the original MB speakers were replaced with no name JUNK, which is the real reason I've decided to replace the entire sound system. The new speakers are Polk Audio db 400 in front and Polk Audio db 525 rear.

Had to do a little corner trimming on the front speakers (easily with back and forth bending with vise-grips). The plastic dash speaker cover is a little snug on top of the center tweeter? but is not noticeable. Rear speakers went in easily after removing the plastic bellows which surrounded the original speakers.

When I removed the Kenwood I saw that whoever put it in did extensive rewiring. The normal blue, red and black wires are no problem but it's the yellow and orange which I can't figure out. The orange-white striped wire has a plastic marker which says DIMMER on one side and ILLUMI on the other.

That variable adjuster at the back of the shifter console would adjust the volume between front and back speakers. I can't figure out how it's tied in. Also I can't locate the rear speaker wires in this tangle. The color codes don't match and after I disconnected the battery I couldn't get a continuity check between any of these wires and the rear speakers.

Does anyone know where a radio wiring diagram is for the W123. I'd like to rip out all this crap out and rewire it.
Attached Thumbnails
Any 123 Radio Wiring Expertise?-1.jpg  
__________________
83 300D 328k mi (623) Light Ivory - daily driver
82 300D 166k mi (881) Thisle Green - fixer upper
82 300D 282k mi (473) Champagne - parts

Last edited by rkohut; 09-07-2008 at 07:48 AM.
Reply With Quote
  #2  
Old 01-23-2008, 07:31 PM
Registered User
 
Join Date: Jun 2006
Location: MA, VA
Posts: 363
I just put the GT520 in mine, and I used the diagram on this thread for help. Getting rid of the fader switch is pretty easy- just peel back the black plastic wire sheath and follow the directions on the thread. It has a good diagram that helped me a lot. I'm not sure the colors will help you, but the wire position may. You can use a small AA battery to find which wire goes to which speaker. The speaker will crackle when it is hooked up to the small battery.

And speaking from experience, tape the antenna connection really well if you are using a cable extension (I put in the XD-100 HD tuner). It fell out when I installed the headunit and was a pain to get out. Also, don't drop one of the two radio removal keys behind the headunit when you install it. It made getting the headunit out to access the antenna cable a PITA.

edit- that is a fader switch, BTW
__________________
Andrew

1989 Volvo 745- 202K
Reply With Quote
  #3  
Old 01-23-2008, 07:54 PM
Jeremy5848's Avatar
Registered Biodiesel User
 
Join Date: Mar 2006
Location: Sonoma Wine Country
Posts: 8,394
New wires

I recommend abandoning the existing wiring and running all new wires. In the 123 body it's fairly easy to do, just lift up the carpets. I replaced the speakers with MB-Quart speakers, there's a thread here somewhere on that project. You can abandon the fader switch in the console and use the controls in the radio so that you have true 4-speaker stereo. I ended up installing a switch in the fader position and wiring it to my garage door opener remote (there's a thread on that, too).

Jeremy
__________________

"Buster" in the '95

Our all-biodiesel family
1995 E300D (W124) . .239,000 miles My car
1996 E300D (W210) . .313,000 miles Wife's car
Santa Rosa population 170,685 (2012)
Total. . . . . . . . . . . . 722,685
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970
Reply With Quote
  #4  
Old 01-23-2008, 08:28 PM
mobetta's Avatar
(Oo{-I-}oO)
 
Join Date: Mar 2006
Location: minnesota,hey.
Posts: 1,840
Quote:
Originally Posted by cavaliers16 View Post
..... You can use a small AA battery to find which wire goes to which speaker. The speaker will crackle when it is hooked up to the small battery....
also you can tell which lead is + this way. use a 1.5v batt- anything from AAA to D cell works. when connected to the batt, if the cone pushes out, the positive lead is on the + of the battery. if it pulls in, polarity is reversed.

orange-wh is for dash lights- will dim when headlites are on- can ignore or tie into the+ side of any lights under the console.
yellow should be switched ignition, red to batt. or vice versa.
__________________
1984 123.193 372,xxx miles, room for Seven.

1999 Dodge Durango Cummins 4BTAA 47RE 5k lb 4x4 getting 25+mpgs, room for Seven.
Reply With Quote
  #5  
Old 01-23-2008, 08:43 PM
registered biodiesel user
 
Join Date: Jan 2008
Location: Los Angeles, CA
Posts: 11
I just did this in a 300TDt a couple weekends ago so the info is pretty fresh in my head. Those 4 speakers wired in parallel with a common ground will provide a 2ohm load to your new head's amp and it probably won't put up with that for very long, plus modern heads have fader controls onboard so I'd recommend definitely taking the factory fader out of the equation and getting all of the wires up to the radio where you wil forever have all the options you need. I didn't run new wires to the speakers - the factory wires were a heavy-enough gauge and all in good condition.

Here's the basics of the factory wires:

Brown = Ground -
Black = Switched Ignition +
Red = Always on + (memory)
Grey = Dash Lights (dimmer)
Blue = power antenna

The speaker wires you'll find behind the radio are;

Red+ Black- Left Speaker (goes to fader on console)
Green+ Black- Right Speaker (goes to fader on console)

To bypass the fader:
. remove the ashtray
. remove the two screws from the ashtray mount and pull that out
. the center console slides back an inch or two and can then be lifted. One mine, the front corners had to be bent slightly (be careful not to break anything) to come out from under the plastic bits and be careful with the back (the end closer to the armrest) - there's a pin at the very rear that goes into a hole in the console mount - if this pin isn't fully free of the hole and you yank up, you'll break something

There is a plug on the bottom of the fader unit that has 6 wires going to it - 4 speaker + and two common grounds. Pull the connector off the switch and snip the wires off the connector and then pull that entire sheathed bundle back up under the console into the hole behind the radio spot. I had to remove a large zip tie near the shifter and there was masking tape around a few of the wire bundles way underneath that I basically had to tug that bundle out of.

Once you have the whole bundle available, carefully remove the sheath from the wire bundle and what you need to do from there is pretty obvious. Clip the connectors at the ends of the wires you find joined and you'll end up with the original red, green, black, black set completely unhooked and 4 pairs of wires that go directly to speakers. I did some extra cutting at this point to make even-length pairs as they were all different lengths in the bundle so that the splice points weren't all in one place. I left the individual pairs different lengths, but do whatever works for you. You'll have plenty of wire to work with when you're done freeing them

I won't mention wire colors - they seemed to vary a lot from year to year and I know at least on mine, the colors were hard to discern anyway. The fronts on mine were pretty obvious; they were the pair that just disappeared left and right behind the dash - the rears disappeared back into the wire bundle under the console. A quick test of one of these pairs told me which one it was which made the other obvious. It was all straightforward butt splices from there on out and everything was good to go.

Last edited by EricLee31; 01-23-2008 at 09:53 PM.
Reply With Quote
  #6  
Old 01-23-2008, 08:44 PM
Registered User
 
Join Date: May 2005
Location: Northern VA
Posts: 225
Quote:
Originally Posted by cavaliers16 View Post
I just put the GT520 in mine, and I used the diagram on this thread for help.
Great link! I found about a dozen radio wiring threads, but not that one. This is what I was looking for.

Quote:
Originally Posted by cavaliers16 View Post
I just put the GT520 in mine, and I used the diagram on this thread for help.

edit- that is a fader switch, BTW
The fader is supposed to?
a) fade the dash lights or
b) move between the front and rear speakers as was improperly? wired on mine
__________________
83 300D 328k mi (623) Light Ivory - daily driver
82 300D 166k mi (881) Thisle Green - fixer upper
82 300D 282k mi (473) Champagne - parts
Reply With Quote
  #7  
Old 01-23-2008, 08:52 PM
Registered User
 
Join Date: May 2005
Location: Northern VA
Posts: 225
Quote:
Originally Posted by Jeremy5848 View Post
I recommend abandoning the existing wiring and running all new wires. In the 123 body it's fairly easy to do, just lift up the carpets. I replaced the speakers with MB-Quart speakers, there's a thread here somewhere on that project. You can abandon the fader switch in the console and use the controls in the radio so that you have true 4-speaker stereo. I ended up installing a switch in the fader position and wiring it to my garage door opener remote (there's a thread on that, too).

Jeremy
Yeah, I'll be doing some ripping out tomorrow in an attempt to restore to original wiring. Thanks.
__________________
83 300D 328k mi (623) Light Ivory - daily driver
82 300D 166k mi (881) Thisle Green - fixer upper
82 300D 282k mi (473) Champagne - parts
Reply With Quote
  #8  
Old 01-23-2008, 08:56 PM
Registered User
 
Join Date: May 2005
Location: Northern VA
Posts: 225
Quote:
Originally Posted by mobetta View Post
also you can tell which lead is + this way. use a 1.5v batt- anything from AAA to D cell works. when connected to the batt, if the cone pushes out, the positive lead is on the + of the battery. if it pulls in, polarity is reversed..
Nice....thanks

Quote:
Originally Posted by mobetta View Post

orange-wh is for dash lights- will dim when headlites are on-
You mean to dim the SUPER bright 123 dash lights.
__________________
83 300D 328k mi (623) Light Ivory - daily driver
82 300D 166k mi (881) Thisle Green - fixer upper
82 300D 282k mi (473) Champagne - parts
Reply With Quote
  #9  
Old 01-23-2008, 09:09 PM
mobetta's Avatar
(Oo{-I-}oO)
 
Join Date: Mar 2006
Location: minnesota,hey.
Posts: 1,840
yeah- I would definitely use the dimmer function- otherwise the radio lites will blind you compared to others.

fader is for speakers....
__________________
1984 123.193 372,xxx miles, room for Seven.

1999 Dodge Durango Cummins 4BTAA 47RE 5k lb 4x4 getting 25+mpgs, room for Seven.
Reply With Quote
  #10  
Old 01-23-2008, 09:38 PM
Registered User
 
Join Date: May 2005
Location: Northern VA
Posts: 225
Quote:
Originally Posted by EricLee31 View Post
I just did this in a 300TDt a couple weekends ago so the info is pretty fresh in my head. Those 4 speakers wired in parallel with a common ground will provide a 2ohm load to your new head's amp and it probably won't put up with that for very long, plus modern heads have fader controls onboard so I'd recommend definitely taking the factory fader out of the equation and getting all of the wires up to the radio where you wil forever have all the options you need. I didn't run new wires to the speakers - the factory wires were a heavy-enough gauge and all in good condition.
.
.
.
It was all straightforward butt splices from there on out and everything was good to go.
EricLee31, thanks for the great writeup, especially concerning the fader wiring.
__________________
83 300D 328k mi (623) Light Ivory - daily driver
82 300D 166k mi (881) Thisle Green - fixer upper
82 300D 282k mi (473) Champagne - parts
Reply With Quote
  #11  
Old 01-23-2008, 10:10 PM
Larry Delor's Avatar
What, Me Worry?
 
Join Date: Jun 1999
Location: Sarasota, Fl.
Posts: 3,112
I just wanted to add, that the "no name, junk speakers" are probably still better than the paper crap that was in there go begin with. Obviously, the MB buyer for those speakers was deaf and blind, or else he wouldn't have put such an embarrassment of a speaker into a Benz.
__________________
It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
Reply With Quote
  #12  
Old 01-23-2008, 10:37 PM
Registered User
 
Join Date: Jun 2006
Location: MA, VA
Posts: 363
Quote:
Originally Posted by Larry Delor View Post
I just wanted to add, that the "no name, junk speakers" are probably still better than the paper crap that was in there go begin with. Obviously, the MB buyer for those speakers was deaf and blind, or else he wouldn't have put such an embarrassment of a speaker into a Benz.
This is true- the MB speakers are pretty weak. The new headunit actually gives them some sound to work with, and they are very poor at moving air. The front ones give zero bass (4") and the rears (5.25") have close to zero bass. I have my headunit's fader at +8 to the back just to get any bass out of the speakers. Compared with the Pioneer ones in our Volvo 740, these sound like junk.
__________________
Andrew

1989 Volvo 745- 202K
Reply With Quote
  #13  
Old 01-23-2008, 10:39 PM
Registered User
 
Join Date: Jun 2006
Location: MA, VA
Posts: 363
Quote:
Originally Posted by rkohut View Post
The fader is supposed to?
a) fade the dash lights or
b) move between the front and rear speakers as was improperly? wired on mine
B- they have a tendency to go bad and ruin the sound from the headunit. My fader took out 3/4 speakers if it wasn't in the all the way forward position. Talk about no bass...
__________________
Andrew

1989 Volvo 745- 202K
Reply With Quote
  #14  
Old 01-30-2008, 04:23 PM
registered biodiesel user
 
Join Date: Jan 2008
Location: Los Angeles, CA
Posts: 11
Quote:
Originally Posted by rkohut View Post
EricLee31, thanks for the great writeup, especially concerning the fader wiring.
happy to help! I've been soaking up so much info from these forums lately, i feel like I have to give back whatever limited info I have so far. I just hope it helps someone in the future... places like this are gold for those of us who like to do things themselves.


Quote:
Originally Posted by Larry Delor View Post
I just wanted to add, that the "no name, junk speakers" are probably still better than the paper crap that was in there go begin with. Obviously, the MB buyer for those speakers was deaf and blind, or else he wouldn't have put such an embarrassment of a speaker into a Benz.
It goes that way with everything, even late models. Most people think those sound fine, especially when they're new. My 01 330i has the factory "premium" sound... 10 Harman Kardon speaker setup, the works. Yup, paper cones. Those got replaced fast.

Last edited by EricLee31; 01-31-2008 at 06:49 PM.
Reply With Quote
  #15  
Old 09-06-2008, 07:39 AM
Dee8go's Avatar
Senor User
 
Join Date: Apr 2006
Location: Arlington, VA
Posts: 7,190
Wire gauge was mentioned above somewhere, but I didn't see a particular gauge noted. What is MBs standard gauge wire for stereo speakers? If you have you car torn apart anyhow, would you replace these wires with someting heavier?
__________________
" The market, like the Lord, helps those who help themselves. But, unlike the Lord, the market does not forgive those who know not what they do."- Warren Buffett

OBK #55

1998 Lincoln Continental - Sold
Max 1984 300TD 285,000 miles - Sold
The Dee8gonator 1987 560SEC 196,000 miles - Sold
Orgasmatron - 2006 CLS500 90,000 miles
2002 C320 Wagon 122,000 miles
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 09:14 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page