I have a 1991 560SEL.

Behind my instrument cluster, I have the wires shown in the attached image. I'm hoping someone can help identify them. I believe this is the main power to the speedo unit. The set on the left was attached to the round speedometer input. The thick black wire was plugged in and the green wire was just hanging loose. The wire on the right has exactly the same end as the wire plugged into the speedometer but wasn't attached to anything. Does anyone know why there would be two wires with the same end? And what is the green wire? Should they be connected to one another? Although they fit together, it doesn't look right.

Any info would be appreciated.

Thanks!

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they maybe for a device you dont have. Does everything work ok?

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1986 300SDL, 211K,Dealership serviced its whole life
1991 190E 2.6(120k)
1983 300D(300k)
1977 300D(211k)

One of the green wires plugs into the speedometer. the other connects to the black wire. The second one connected to the black wire supplies the speed signal to other things in the car that need vehicle speed such as ABS, cruise, etc.
Paul

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84 500 SEL (307,xxx miles)

Everything was working until the other day. The speedo and odometer stopped working 34 miles short of 200K!

There are two BLACK wires with identical female ends that would fit into the speedometer connector on the cluster. One of those Black wires has a little pigtail GREEN wire coming out with a male end. This black wire was plugged into the cluster. The little green wire coming from it was not plugged into anything.

I saw the other black female connector was empty so I assumed the geen wire went there. Nothing changed. I'm wondering if the speedo itself went bad and these wires are not needed. But the car is loaded, ABS, cruise, etc. So I don't know why they wouldn't be used. Even the radio volume is supposed to change with speed, although I don't think that happened. Maybe that was what the extra wires were for. I had a shop test the incoming voltage to make sure there was a signal coming to the speedo from the trans and it checks out ok. I guess I won't know until I have the cluster itself looked at.

Anyone have a recommendation for instrument repair? I found these four after a brief search online:

http://www.speedometer.com
http://www.mbcluster.com
http://www.dnaspeedometers.com
http://www.mrwhizard.com
http://www.instrumentclusters.com