Frisbeeman

I have an aftermarket trailer hitch and wanted to do the wiring and plug for trailer lights. In searching posts I found several folks writing that the only choice is to get the Mercedes hitch and electrical module. It turns out there is an aftermarket alternative made for the 06 - 08 ML350's. Curt 56200 is a powered trailer light converter that works for 06 - 08 ML 350's. It doesn't use the vehicle tail light circuits to power the trailer lights. For instance the brake light. When the vehicle brake light lights there is a wire from the Curt converter to the vehicle brake light, but its only a 1 milliamp draw to tell the converter the vehicle brake light is illuminated. The converter then draws power directly off the vehicle battery to illuminate the trailer brake light.

My problem is, I am having trouble telling which wire is which in the tail light assembly. Can someone tell me so I know which converter wire to hook to each vehicle wire? I know it’s a PWM system. The sockets are numbered in the plug you can disconnect from the tail light. Can someone tell me which wire is which?

Thank you.

GregW / Oregon

No, but a multimeter and friend operating the various lights would make quick work of identification.

p1800tg

Just had my mechanic install the 56200. Picked up all the wires and power from the rear power box, but you need a test light and meter. Also you may want to install inline fuse. I pull the fuse out when I am not using the hitch, one less thing on the system You can call Curt for help tey are very helpful.

hhj6666

I know this topic has been killed but I am up against a huge deadline.

Has anyone installed the Curt 56200 in a ML350? The Brake/tail wire out of the converter is one wire but the tail lights have a separate brake and tail light. Does anyone know which wire the brake/tail wire from the converter must attach to? I am desparate for help on this one....many thanks!

-Hans

Mike Butler

Or you could have done that and posted the results.

Mike Butler

I'm not familiar with the 56200, but here are the color codes on the car, for each plug, from the top on down.

LEFT
Orange=Ground
Black=Turn
Pink=Stop
Gray w/Black Tracer=Tail

RIGHT
Orange=Ground
Green=Turn
Purple=Stop
Gray=Tail

That’s all I know.

thunderbirl

This is a link to an earlier thread which may be helpful. (look at #6 in the thread)

I was not able to use the 56200 module in my 2008 W164 ML350. The thread above explains that a different module was needed, why it was needed and exactly how it all worked out.

By the way, it's still working great!