Will German Vehicle 7-Way to 4-Way Adapter # C35FR Cause Error Messages without Trailer Connected

Question:

I read you qandA no, 95119 but still have a question. When I plug in my 7/4 adapter, without the trailer connected, I get various combinations of flashing error lights on the adapter depending on what action is being taken. Should I get flashing lights on the adapter when the trailer is not hooked up? This same adapter works fine on my 4runner and trailer.

asked by: Fred

Expert Reply:

Sounds like you are using the 7-Way to 4-Way adapter part # C35FR which is designed for German vehicles like your 2011 Mercedes ML350 towing trailers with LED lights to prevent error codes on the dash. Without a trailer connected to the adapter you may have some issues like you mentioned but as long as it works when a trailer is connected you should be fine. You'd just need to unplug the adapter when not towing and you'd be good.

expert reply by: Jameson C