Recommendations To Solve LED Trailer Lighting Issue With 2007 Mercedes Benz ML500

Question:

i have a 2007 MB ML500 with factory hitch, wiring and SAM module. for some reason the car will not light up my new Aluma MC10 trailer with LEDs. i dont want to spend over $700 fixing the car, can i use the Techonsha wiring kit as another alternative? would using this cause any issues with the car electronics?

asked by: Ed

Expert Reply:

If your vehicle already has a working 4-way, then I recommend using the Diamond LED Light Bulb Load-Resistor Kit # DI34ZR on your trailer. These load resistors create more draw on your wiring to resemble an incandescent light pull for the LED lights that require far less power. You will need 3 of these on the trailer side of your 4-way connection.

If you don't have a 4-way on your 2007 Mercedes Benz ML500, I recommend the 4-Pole Trailer Connector and Installation Kit # C59496. This will give you a working 4-way trailer connection that may or may not still need the load resistors on your trailer to make connections work properly.

If you have a working 7-way trailer connection, you can use the Trailer Connector Adapter w/ Lamp-Out Sensor Bypass - 7-Way RV to 7-Way RV - Vehicle End # 20142 to solve your LED connection issues. This adapter creates a draw like the load resistors to make your LED trailer function correctly.

expert reply by: Jason S