hi there, new here and at my wits end, i bought for my 2000 clk 320 a audio 10, be 3100 and a cd changer unit as the car came with a competely out of place sony unit. i`m told this was equipment this car would or could be fitted with as i have the controls in the steering wheel. i went to fit the unit and found that the two bottom plugs for speakers and power were there but not the top one for steering wheel and cd changer, i`m just left with 5 wires brown, blue, red, black and black and white. I would love to know how they go to the five pins. yours gratefully Paul