the yellow black wire comes from the factory phone and is a - trigger wire to mute the stereo(phone mute).

The green black is the speed pulse wire (vss) to allow the factory radio to adjust the volume by the speed of the car. (also used when installing a navigation system)

The light blue brown is the alarm trigger wire (not used in aftermarket install)

All the wires in the gray harness are the stock tuner's data cable that appears to be cut off and the wires are being used for other things. I would have to say for you to see what is hooked up in the trunk at the other end of the gray cable (will be on the drivers side by the antenna).

The gray purple wires should be the illumination wires but might not adjust with the dimmer control.

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The Mercedes Specialists Since 1986