trailer lights
 

Hello, I just bought a 2018 GLC300 for my wife. My first MB. Very nice driving car and so far she likes it more than the Lexus that got totaled several weeks ago. Luckily no one was injured. I ordered a hitch for the car. I am not planning to do any towing, but she uses it to bring the trash can down the driveway, and occasionally we need it for something else. The light kit that etrailer sent will not fit my car as mine has the premium 3 package. Anyone dealt with this before? I am not crazy about splicing into the harness as the wires are very light. I would prefer plug and play. I may just wait a while and see if someone makes a kit for my application in the future. The dealer said they send cars to Uhaul for hitches and lights. Not sure if I want them hacking into the harness! Any thoughts? Thank you.

Check www.carid.com regarding trailer wiring for your vehicle.

Thanks, I checked them out and they have the same kit as e-trailer, which will not match up to my wiring.

I would find a dealer who would install per factory specs...sending you to U-haul is a terrible move on your current dealers end...

Agree!

The last summer, I install this part for the trailer light and it's work good
https://www.curtmfg.com/part/56146

The more difficulty is to connect on the wire of the light, It requires removing the right and left rear lights for connect the wires.

^^^I believe the OP is looking for a 'factory' plug & play option...there are multiple aftermarket 'splicing' options but, this could lead to integration issues.

They do make a plug and play kit but it will not work with my car because it has the Premium 3 package and appears to have different tailight connectors.

Me I use this doc for make my installation, because the color code is include:
https://cdn.shopify.com/s/files/1/21...34328933424291
It's not a plug and play, but I think it's work with the Premium 3 package because you have just some more sensor, not more light. I thing it's just more complicated for install the hitch (for remove bumper), because you have some more sensor on bumper.

Thanks Frandumont, that color code may be useful if I end up going with a splice kit. I already have the hitch installed, that was pretty easy. No hurry for trailer lights, so I am going to give it some time to see if someone makes a kit in the near future. I believe the difference in the premium kit is different connectors at the tail lights among the other stuff.

Just go "spliceless".... https://www.etrailer.com/Custom-Fit-...119250KIT.html

Wow, that is a cool kit! Thanks.

And "spliceless" is transferable to another vehicle down the road ... it's the "new path"... keep the beat !

You probably know that wiring harnesses are not like they used to be in the old days where you could simply tap into an existing 12volt brake light line and a 12 volt tail light line. Now days the wires carry pulse width modulated (PWM) signals and one wire serves multiple functions via one bulb. I wired a Curt PWM module into my GLK350 in which one bulb receives the equivalent of either an average of 4 volts or 12 volts depending on whether it is serving as a tail light or brake light. I'm pretty confident that your vehicle will have a similar arrangement. You'll find a writeup of my installation here:

https://mbworld.org/forums/glk-class...asier-way.html

I believe you will find the PWM module for your GLC300 here:

https://www.curtmfg.com/towing-elect...ght-converters

Hope this helps

The new generation "spliceless" is specifically PWM compatible - with "spliceless" you make direct battery hookup to the module - the sensors create no interference or capacitance changes to your rear wiring at all ....... another bonus is the whole "spliceless" rig is transferable to your next vehicle .. no worries ..

And what about car warranty? If I will splice the wires to connect CURT 56146 or Tekonsha 119147 - will I have any problems with Dealership?

You won't have any warranty problems with MB on a correct installation of the Spice-In Modulite - but if you muck up the Modulite install - or have Modulite problem down the road (and Modulite is very reliable) you will need a hitch/trailer specialist fix it for you - MB dealer won't be able to help.

Frankly - for like $160 more - I love the "spliceless" since I can always move it over to my next vehicle