Trailer LED Lights Not Working when Connected to a 2012 Mercedes ML350
Question:
Good day I have a 2012 ML 350 and just bought a caravan with Led lights. How can I fix it as the Leds domt work
asked by: Deon
Expert Reply:
This is a common problem with Mercedes vehicles and trailers that have LED lights. Basically the LED lights do not draw enough power for the vehicle to recognize they are there and sometimes they sense it as a burned out bulb so you might see an error message displayed in the vehicle.
One option is to use a special adapter, # C35FR for a 7- to 4-Way or # C57003 for a 7- to 7-Way. These adapters have load resistors to simulate incandescent bulbs so the LED lights will work.
If the Mercedes has something other than a 7-Way trailer connector (US style where the turn signals and brake lights are combined on the same circuits) then there is still a way to provide more load on the affected circuits. You can install load resistors such as # DI34ZR for a pair, on the trailer wiring. The load resistors will essentially simulate incandescent bulbs and allow the trailer LED lights to work when connected to the vehicle.
Products Referenced in This Question
7-Way to 4-Way/5-Way Trailer Adapter for Vehicles with Lamp-Out Sensors Towing Trailers with LEDs
- Trailer Wiring
- Wiring Adapters
- Multi-Function Adapter
- 7 Round - Blade
- Plug Only
- 5 Flat
- 4 Flat
- CURT
more information >
7-Way Trailer Adapter for Towing Trailers with LED Lights
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Custom Fit
- 7 Round - Blade
- CURT
more information >
Load Resistor Kit for LED Turn Signals - 50 Watts - 6 Ohm - Qty 2
- Accessories and Parts
- Trailer Lights
- Load-Resistor Kit
- Diamond
more information >
Product Page this Question was Asked From
ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Converter
- Universal Fit
- 4 Flat
- Tekonsha
more information >
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