Functions on the Output Side of 7-Way to 5-Way and 4-Way Trailer Adapter for German Vehicles

Question:

I see the male then four female outputs on this adapter. I specifically need ground, 12v, and backup. I believe this would be pin 7 ground, pin 1 reverse or backup, and pin 4 12v. On the flat output connector how would I get to these corresponding pins that are on the 7-way plug? I am looking to use this to connect a White Night Light that mounts on my trailer hitch. I need to fool the 2013 Mercedes GL450 to think it has a full trailer hookup. It looks like this will provide the needed load resistance. Thanks for you help on this one.

asked by: Steve M

Expert Reply:

On the 7-Way to 5/4-Way adapter, # C35FR, for German vehicles, you are only going to have the basic lighting functions on the 4/5-Way side (left and right turn, running lights, brake lights). The 5-Way will also have a reverse light function if that circuit is functional on the 7-Way. But it does provide additional load to take care of that bulb out sensor issue that plagues newer German vehicles like your 2013 Mercedes GL450.

The other option is to install load resistors, # DI34ZR, in line on the affected circuit. These will draw more power as well and will fool that bulb out sensor. Sometimes the adapter does not have enough draw and adding a load resistor like this will take care of the issue.

expert reply by: Michael H