Hello, I have a problem with my trailer socket. I noticed that when I use a trailer with LED lighting, the brake lights flicker/flash slightly as soon as I connect the trailer to the vehicle. But all the lighting works perfectly.

When I check PIN 6 (brake light, 13-pin junction box) on the vehicle-side trailer socket with a 12V multimeter, it also flickers/flashes. So the problem is with the connection, not with the trailer.

What can I do? Is the trailer module defective? I checked the other connections, the others don't flicker. The brake light also works perfectly.

Thank you very much!

You can get a unit that plugs into your wiring harness between the trailer and vehicle. Provides extra resistance so the ECUs detect a trailer. I got one but rarely used it as it didn't seem to make any difference.

There may be a more sophisticated LR solution though. MY11 SD4 SE Auto

Hello, I know this plug. The lighting also works without it on all vehicles.

I checked PIN 6 (brake) with the multimeter on other cars. In none of the cars did the contact in the socket flash/flicker.

As soon as I unlock the Freelander, there is power on PIN 6. If I lock it again or after a long time without opening a door, PIN 6 goes out.

I don't even know what that would be good for. Otherwise I'll have to ask my workshop tomorrow.

Hello, I found the solution.

I checked the contacts with an LED tester. All contacts that are responsible for the lighting are flashing.

I then found the solution on the Internet from "Erich Jaeger", a large manufacturer of trailer electrical technology. They write that the trailer sockets send out a test signal for trailer detection and that is why LED test devices flash. To test the socket, you should use test devices with 21W light bulbs.

That's why the LED tail lights on my trailer also flash, but not the lights that contain light bulbs, e.g. side lights or license plate lights.

The adapter plug or resistors will probably help as a solution.

It's not the vehicle but the trailer. Likely cheap LED lights without a dropper resistor.

I tend to just add a separate dropper resistor into the trailer harness to sort out the cheap LED lights I tend to put on my trailers.

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