ZedStyle

i'm struggling right now!

i think i figured out the spreaker wires.
for the rest, i think the red wire is the power, brown is ground, and black is the amp turn-on??? I think the red with the yellow stripe is the ACC. I also have TWO blue ones with white stripes, and one black with a whitish greyish stripe. ideas??

YNVDIZW124

I said this 10 post before....do you have a test light?

Bigpete123

yeah dude. Just spend the $10-15 and get a voltmeter at Radioshack. Get one of the digital ones with the dial thingy on it. When you get it, turn it on, touch the red pen-like thing to a wire in question, and the black pen-like thing to a metal part of your car. When you find a wire that gives you 12 constant volts (it may fluctuate very slightly), you've got your power. Mark that wire, then unplug the negative terminal on your battery. Connect your deck to the alleged power, ground, and remote turn-on cables **MAKING SURE YOU HAVE AN INLINE FUSE ON THE POWER CABLE FIRST**, plug your battery back in, and turn the key in the ignition. If the deck turns on, you're golden. Your first hint on the power cable thing should be an inline fuse on the wire. There may be a few that have them, but it will narrow things down for you.

If you're not sure which wire is the remote turn-on wire, use your voltmeter again. With the battery connected, put your key in the ignition and turn your key to the "ACC" or accessory position. Touch the red terminal on the voltmeter to the wire in question. If you get a reading on the voltmeter, keep it connected while you turn your key off. If the voltage drops to zero in correlation with turning off the key, you have your remote-turn on lead.

I have to disclaim this though. I'm not a professional, so use your best judgment. www.mercedesshop.com has some great forums. If you haven't tried them out, spend a couple hours clicking around over there and you might find what you're looking for. Let me know if this doesn't make sense.

Good luck.

ZedStyle

cheers guys! i need to go buy some connectors and what have you from radio shack, so i'll see about picking up one of those voltmeters.
i found this in the mean time:

http://www.beckerelectronics.com/1492.html

so the installation continues tomorrow! even though i also just realized i might have ordered the wrong size of speakers for my front doors... they get here next week, i guess i'll know for sure soon!

Bigpete123

make sure to label your wires when you figure them out, too! That link looks very useful, assuming you didn't cut the wires from the connector

YNVDIZW124

I think you guys missed my post...takes 10 min to install an aftermarket stereo on a w124....

Bigpete123

heh, oh yeah. I wouldn't have wasted my time posting if I had realized that was there. super.

ps2cho

YNVDIZ, I just bought a pioneer HU today from bestbuy and I would like to do the installation myself....

On my TE I had it installed professionally and they used an adapter...are you saying its possible to avoid spending the $30 on the adapter? Is the plug that goes into the back of the OEM Becker unit the same size+shape as the one that goes into aftermarket HU's?
I'd like to get all info before I pull her out as I plan to get all my wires down for the amp too. Any tips on getting the wires into the trunk on the sedan? My wagon was easy obviously...

YNVDIZW124

Don't they install it for free?

No, it's not the same. All you need to do is to find power, ground, power antenna, and remote cables from the stock radio harness. You can buy a wire stripper tool to expose and be able to tap into those wires. You can either solder or just tape up an extra set of wires leaving your oem adapter uncut. You will have to run new cables to the speakers because the stock cables run through the fader so it won't work with an aftermarket HU.

You can take off the passenger door sills, plastic cover on the bottom of the b pillar, and remove the back seat. What I did was to take out my passenger seat and ran the cables around the trans tunnel and to the side. Use a coat hanger to route all the cables where you can't reach with your hand.

ps2cho

Okay gotcha...wiring doesn't seem that bad for the basic harness....I am still a little confused over the fader though.

Can you explain to me why the fader won't work with the aftermarket HU? Why can't I use the fader? My TE still has the fader functional. I understand the built-in fader on the HU won't work with the fader on the console and vice versa. I'd rather not run new cable to the rear speakers if possible.

Any recommendations on a cheap amp wiring kit? I used the complete 8 gauge KnuKonceptz set before in my wagon and it worked out well...but they increased their prices by quite a bit since I last bought from them. I paid $16 for the whole kit in 2007 and right now the same kit is $25.

I plan to build a small enclosed box and have one single 10/12" sub on like a 300W amp. Nothing crazy at all. Just cheap n cheerful like the wagon has.

2PHAST

Your factory head unit is two channel, which feeds into a rotary fader which splits the signal into a four channel configuration. Your new head unit is four channel, so you would want to bypass the fader completely to use all four channels of your new headunit.

Some cheesy audio dealers will just use two channels of your head unit and run it through the OE fader. You run the risk of burning up the fader (not rated for high power) and you lose 50% of your new decks output power.

Its actually easier to just run new speaker wire, but if you just dont want to do it, what you will need to do is pull your console and get access to the speaker wires that come off the fader (output side), should be four sets, you can cut them anywhere after the fader and splice in some new speaker wire and run it up to the dash area where the deck is. I don't recommend this method though as the OE wire is 18awg and you should really be using a minimum of 16awg.

This diagram should help you understand how the OE system is designed.

forcedawd

Here is a pretty good post for the early 124's indicating how to bypass the fader -

Fader Bypass

ps2cho

awesome

I'll let you guys know how it goes.

ps2cho

I just realized you didn't mean having to run new wires all the way to the actual speaker ....I will bypass the fader then!

Silly me...

Gonna try and get it working today. I'll take some pics for a DIY article maybe.

EDIT: I think I just found the W124 stock wiring diagram.

YNV does this look right to you?
http://www.the12volt.com/installbay/...tail/1416.html

Is there any way to test to see if a speaker is blown? My right speaker doesn't work at all...I might just replace them all anyway, but for right now if I could get it up and running that would be great.

YNVDIZW124

2phast is right on the money. You can run new wires to your front speakers and connect the other two channels to the O.E wires and bypass the fader. I ran new wires for the amp so i also connected the speakers that way too. I took my fader apart and made it an on/off switch for my bass amp so it still does something. On 94/95 models you need to run ne cables because you need to bypass the factory amp.

2PHAST

Actually, the 94/95 W124's are much easier, as the head unit is four channel with built in fader for front/rear, so there is no manual fader and no need to rewire.

As for the amp, the 94/95 is also almost identical to the 92+ W124, where as the head unit powers all four speakers (front dash and rear deck) and there is a small amplifier in the rear trunk that powers the sub's in the door. Now if you want to retain the OE amp, it takes high level inputs from the headunit and these inputs are tapped off of the OE dash wires, so if you rewire your speakers, you need to located the inputs for the amp and wire those up also. If I remember, there is some sort of Y connection back in the dash somewhere where this occurs. Most after market installs don't address this, so the door speakers don't end up working.

The 400e/500e had two amps back in this location vs. the single amp of the other models. There are two descriptions for the different sound systems, the "Active Loudspeaker System" and the one in the 400e/500e which is just referred to as "Sound System".

The pre 94 models are the ***** because of the manual fader AND the fact that the Becker is a two piece unit, with the tuner in the trunk, so you know what that means....no antenna plug in the dash, so if you want a radio when you install a new head unit, you get to also run a new antenna wire!

ps2cho

I have the headunit out and the wires exposed...but the colors dont match to what you said above.

I have a Grey/Blue, Red/White, Brown, Black/Yellow

Obviously the brown is still ground...but what about the others?
The new headunit has its own ground...do I leave the brown unconnected then?

YNVDIZW124

red/white should be acc ( ignition ), black yellow is constant 12v, brown is ground, blue is power antenna.

I made a mistake years ago when i posted that because I forgot i used gray for the ignition wire. You don't use the gray/purple.

ps2cho

Ok I got conflicts here..
http://www.the12volt.com/installbay/...tail/1416.html

This says red/white is constant +12v

When it comes to the front speakers -- There is a green+black for right speaker, and red+black for left speaker. I assume black = ground, right?
I'm just double checking everything here as this is the first time I've done this...I feel totally confident as long as I got the right connections laid out for me.

YNVDIZW124

This is how it's connected on my car right now after I went to check..... Yellow = red/white, Blue = Blue, Red = Black/yellow, Black = Brown.....

I also ran longer wires to make sure in the future any new HU will be easier to connect. BTW, I have fuses on all the power cables just in case.

There's no possible way you can mess up. If you short something out you'll just blow a fuse. If you connect the wrong power wires, the stereo will turn on but not keep the memory so just swap the wires and that's it.

ps2cho

I tried just seeing if it would turn on and I got no power.

Look at this...what is this plug? It was connected into the back of the becker unit...I can't figure out what it goes to. Maybe this plug is something to do with why its not turning on? Could this be the power antenna/Auto-Antenna Relay? Its the only wire remaining that I have not attached yet to the HU wire connector. That still wouldn't explain why it isnt turning on though would it?



Also not sure what the blue/white goes to as I don't have a blue cable attached the HU wire.

YNVDIZW124

Your HU should have a blue wire for the power antenna....strip back the black cover and see if it's blue? check the fuses...and btw, you should run fuses to the headunit.


ok, just checked again and that wire with the circle should be the power antenna cable.....everything else is how i described...

ps2cho

It has a blue wire called Remote? I thought that was for the amp though?

So let me clarify -- Do the front speakers go straight to the headunit for the stock becker system, or does it go through the fader first?

I switched the constant and ignition power wires and I'm still not getting any power...
Any ideas? The stock headunit was powering on today...

YNVDIZW124

I use the ignition wire or acc wire to turn on the amp. You use that blue wire for the power antenna. Is the fuse ok? I don't know why it wouldn't turn on...maybe a bad ground...are you using a test light or multimeter?

Like 2phast said...

Just run the two channels straight to the speakers and tap into the wires before the fader for the rear speakers.

ps2cho

I bridged the ignition + constant and the cd turned on...woo!

So I am not getting any power to the ignition. I checked it /w DMM too. No voltage. I swapped fuse in the fusebox too.

Any ideas?