GLK-Class (X204) Produced 2008-2014

Curt 56146 trailer hitch 4 way wiring install into 2014 Mercedes GLK250

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Old Jul 26, 2018 | 10:27 AM
  #1  
C300fan2's Avatar
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14 GLK 250
Curt 56146 trailer hitch 4 way wiring install into 2014 Mercedes GLK250

Just completed the install of CURT 56146 Powered trailer wiring into the GLK250 with Led lights.

I needed a fuse tap and some wire to complete the install. I also covered the wire with wire loom just for protection and presentation.

Wiring is as follows:

CURT UNIT --------------------------------------------------MERCEDES

WHITE AND RED (ground) ---------------------------- Vehicle chassis ground
BLACK (12v power)-----------------------------------------FUSE TAP AND FUSE 76 (socket rear) at rear fuse box
GREEN (passenger turn signal)-------------------------BLUE at passenger side light connector
BROWN (taillight signal) ---------------------------------Light blue/ Blue line at passenger side connector
YELLOW (drivers side turn signal) -------------------- PINK at drivers side light connector

The unit is meant to be installed on the drivers side but I installed it on the passenger side under the tail light connector. Because of this i used the extra green wire to extend to the drivers side light connector, that's why thew wire is also green and not yellow.

And here are a few pictures:








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Old Mar 20, 2020 | 12:20 AM
  #2  
mono4lamar's Avatar
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2013 GLK250
Originally Posted by C300fan2
Just completed the install of CURT 56146 Powered trailer wiring into the GLK250 with Led lights.

I needed a fuse tap and some wire to complete the install. I also covered the wire with wire loom just for protection and presentation.

Wiring is as follows:

CURT UNIT --------------------------------------------------MERCEDES

WHITE AND RED (ground) ---------------------------- Vehicle chassis ground
BLACK (12v power)-----------------------------------------FUSE TAP AND FUSE 76 (socket rear) at rear fuse box
GREEN (passenger turn signal)-------------------------BLUE at passenger side light connector
BROWN (taillight signal) ---------------------------------Light blue/ Blue line at passenger side connector
YELLOW (drivers side turn signal) -------------------- PINK at drivers side light connector

The unit is meant to be installed on the drivers side but I installed it on the passenger side under the tail light connector. Because of this i used the extra green wire to extend to the drivers side light connector, that's why thew wire is also green and not yellow.

And here are a few pictures:







I have a harness that separates the taillight and the brake. I would assume that the turn signal (of either side) would be a good input for the trailer module?
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Old May 30, 2021 | 05:34 PM
  #3  
NCWolverine's Avatar
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2015 GLK 250
Were you able to sort out the separate taillight and brake connector situation?
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Old Feb 3, 2022 | 08:50 PM
  #4  
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2006 Ram HD Diesel, 2010 Forester, 2015 GLK250, 2019 Bullitt, a few dirt bikes
[QUOTE=C300fan2;7512791]Just completed the install of CURT 56146 Powered trailer wiring into the GLK250 with Led lights.

I needed a fuse tap and some wire to complete the install. I also covered the wire with wire loom just for protection and presentation.

Wiring is as follows:

CURT UNIT --------------------------------------------------MERCEDES

WHITE AND RED (ground) ---------------------------- Vehicle chassis ground
BLACK (12v power)-----------------------------------------FUSE TAP AND FUSE 76 (socket rear) at rear fuse box
GREEN (passenger turn signal)-------------------------BLUE at passenger side light connector
BROWN (taillight signal) ---------------------------------Light blue/ Blue line at passenger side connector
YELLOW (drivers side turn signal) -------------------- PINK at drivers side light connector

The unit is meant to be installed on the drivers side but I installed it on the passenger side under the tail light connector. Because of this i used the extra green wire to extend to the drivers side light connector, that's why thew wire is also green and not yellow.

And here are a few pictures:







@ Q300 Fan, seems to me you are explaining the wiring in reference to the curt colors, can you share what colors to what on the Mercedes plug side do? I.e drivers side signal wire is pink, what are the colors on that plug for tail light and stop light?
Appreciate any help. Cant find a 2015 GLK250 tail light wiring diagram. Thanks.
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Old Feb 3, 2022 | 11:38 PM
  #5  
C300fan2's Avatar
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Member
10 Year Member
 
Joined: Mar 2015
Posts: 239
Likes: 39
From: Vancouver
14 GLK 250
[QUOTE=SquareBox;8505704]
Originally Posted by C300fan2
Just completed the install of CURT 56146 Powered trailer wiring into the GLK250 with Led lights.

I needed a fuse tap and some wire to complete the install. I also covered the wire with wire loom just for protection and presentation.

Wiring is as follows:

CURT UNIT --------------------------------------------------MERCEDES

WHITE AND RED (ground) ---------------------------- Vehicle chassis ground
BLACK (12v power)-----------------------------------------FUSE TAP AND FUSE 76 (socket rear) at rear fuse box
GREEN (passenger turn signal)-------------------------BLUE at passenger side light connector
BROWN (taillight signal) ---------------------------------Light blue/ Blue line at passenger side connector
YELLOW (drivers side turn signal) -------------------- PINK at drivers side light connector

The unit is meant to be installed on the drivers side but I installed it on the passenger side under the tail light connector. Because of this i used the extra green wire to extend to the drivers side light connector, that's why thew wire is also green and not yellow.

And here are a few pictures:







@ Q300 Fan, seems to me you are explaining the wiring in reference to the curt colors, can you share what colors to what on the Mercedes plug side do? I.e drivers side signal wire is pink, what are the colors on that plug for tail light and stop light?
Appreciate any help. Cant find a 2015 GLK250 tail light wiring diagram. Thanks.
the Mercedes Colors are referenced as well first the curt color then the “……….” Then the Mercedes Color and location
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Old Feb 3, 2022 | 11:48 PM
  #6  
SquareBox's Avatar
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Joined: Jan 2022
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2006 Ram HD Diesel, 2010 Forester, 2015 GLK250, 2019 Bullitt, a few dirt bikes
[QUOTE=C300fan2;8505773]
Originally Posted by SquareBox

the Mercedes Colors are referenced as well first the curt color then the “……….” Then the Mercedes Color and location
Thank you, I see that now on the computer, not so clear on the phone. Would you know what color the break lights are on the plugs? Thanks again.
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