I have a new after market radio and I have a speaker wiring diagram for the car.

I am planning on measuring ohms of the left and right speaker's. Since each of the two speakers on each side are wired together I assume it will lower the ohms and could be to low for the aftermarket stereo.

I know what wires are at the fader, but where are the neg wires hooked together at?

Anyone?

I assume the W126 uses the same radio and fader set up as the W123's of the same age.

The L/R speaker wires connect to the factory radio via the plugs. The colored wire goes to the fader. The black wire (negative) goes to a solder joint in the harness. In the W123 there are two joints a few inches from each other lengthwise from the radio. These are maybe 18-24 inches back from the radio connector.

Also in the W123 the rear speakers PLUG into the fader/radio harness after the fader. If the W126 is similar you may be able to remove the console, find the wires and simply unplug the speakers. You end up with two simple color+black pairs to rear. You would still have to cut the OEM wires to the front unless you ran new ones.

The negative-wire solder joints are listed as S1 and S2 in the pic. It's a tough pic - they're between the speakers; L/R respectively.

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Cool,

I already have that same diagram and I got the wire routing.

You told me what I was looking for, I just need to look for where the negative wires are joined into one.

I was hoping I didn't have to take apart to many consoles.

Thanks for the help, and I'll see where I get this weekend.

Got it done...and it was easier than I thought. Thanks for the help Yak, you saved me time hunting around.

Turned out that I was able to locate the solder joints and cut the grounds by the shifter and fader.

Cut the fader out and bought some speaker wire to extend all the wires up to the dash.

It was fairly easy...and I tested thoroughly with my wiring diagram and battery in hand.

Done deal.