Installation of Zero Contact Interface Sensor Trailer Wiring Harness on 2015 Mercedes-Benz GL-Class

Question:

Hi, I purchased 119250KIT wiring kit for my 2015 Mercedes-Benz GL-Class back in January. I intend to install this soon and the instructional video seems to be straight forward for my vehicle. The question I have is about the wiring of the power. My plan is to not have the kit active all the time, and it will be kept in the spare tire compartment instead of hanging outside. I have a cigarette lighter in the back. Is it possible to just use the cigarette lighter socket, with a cigarette lighter plug, to power the unit? Instead of running the power wire to the battery. Thanks.

asked by: Alexander N

Expert Reply:

For the ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit # 119250KIT should not be installed tapping into another power supply like a cigarette lighter. The power draw needs to be directly from the battery to ensure you don't have a power issue from a fuse or other component that isn't designed for that use. Having power to your trailer wiring even when stored is not an issue and you don't want to keep turning power on and off to a controller like this as it could cause premature failure.

You don't need to worry about the power draw on this unit killing your battery as the draw when not in use is almost nothing and the draw in use is just a few amps for each function which your alternator won't have any issue with.

expert reply by: Jason S