I just bought a new 6x4 trailer and it has LED tail lights, when I plugged it into the trailer plug on my BMW X5 the trailer lights started flickering so I turned the ignition off, pull the key out and the trailer lights still continued flickering, I was told that this is a common occurrence on European vehicles.
So I started researching and found an LED trailer module for $229.00 on Ebay, that sounded a bit expensive so more research and there is a video on YouTube that shows how to do modification with tiny resistors, they are sold in batches of 100 for just $10.00 (Delivered), photo herewith, they have to be this type.
NOTE: DO YOUR OWN RESEARCH FOR YOUR TYPE OF VEHICLE
I fitted one end of each resistor wire into the trailer plug wiring connectors, STOP, LEFT, RIGHT & TAIL LIGHTS and the tail end of all 4 resistor wires together into the white earth connection and made sure they were screwed snug, amazingly it stopped the flickering. If you do this make sure you do it to the trailer plug and not to the car.
