I've just bought a '99 ML320 with factory fitted tow pack. The socket for the lights is different to the standard one here, so I want to change it rather than the plugs on 3 trailers. Can anyone tell me the correct colour codes for the wires in the socket, about 9 in all?

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'66 W100 600 SWB
'05 W463 G55K AMG
'91 W126 500SEL
'93 W463 300GDL
'84 W460 280GES
'83 W460 300GDL
'66 W111 220SEb Coupe
'58 W121 190
'58 W180 220S
Have previously owned '99 SL600, '99 ML320, '79 450SLC, '79 450SEL 6.9 x 2, '68 600, '91 190E 1.8, '90 190E 2.0, '85 190, '90 500SL, '92 500SEL, '97 E300Turbodiesel, '91 300D, '72 280S, '82 300D, '81 300SD, '85 230E, '56 220a and I'm sure I'm forgetting some.

Since no one has answered your post yet, I'll take a stab at it...

I don't know the color codes as I don't have a tow package. But I DO have a multimeter.

Most standard trailers in the US use four wires (and two of those are a common ground). The ground (earth) leads are brown. The left and right taillights are green and yellow respectively. There is usually an additional white wire with a clamp that is independent of the harness. This one clamps to a metal potion of your truck for additional ground (earth) integrity (new trailer balls usually inhibit good ground).

Here's where the multimeter comes in. Connect the negative lead to one of the pins with the brown (doesn't matter which) wire on the ML connector.

Use the positive lead to test the remaining pins...have someone get in the ML and turn on the headlights, hit turn signals, apply brakes, etc, etc. I am guessing each pin performs a specific function, so you will have to splice several of the connections to either the green or yellow wire on the trailer connection.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

On US versions, the hitch comes with an adapter for the trailer harness

Gilly

Thanks for your input guys.
Gilly, would it be possible to see a photo of the US adaptor?? Maybe that's what I need.

Eddie
I don't have one to show or shoot a photo of, maybe one of the other members can do this. I don't have a digital camera either.

One other thing I thought of is on the spring loaded cover over the existing terminals is a layout of what the pins all do, so if an adapter is something you can't come up with, there should be enough info on the flap to help you wire it yourself.

Gilly

Gilly,
I didn't notice that. Thanks. I'll have a look over the weekend.