Thread: Electric Trailer Brakes

You have a euro spec plug on the D4 where the lead that would normally operate the brakes operates one of the tail lamps - on the spec trailer plug you have one lead works the left tail light and the other lead operates the the right tail light.

Do a read of the posts in this thread and all will become clear. Your auto elect should have sussed this out during installation. (I have the same issues in my RRS and is the next thing to fix)

Garry

Originally Posted by garrycol

You have a euro spec plug on the D4 where the lead that would normally operate the brakes operates one of the tail lamps - on the spec trailer plug you have one lead works the left tail light and the other lead operates the the right tail light.

Do a read of the posts in this thread and all will become clear. Your auto elect should have sussed this out during installation. (I have the same issues in my RRS and is the next thing to fix)

Garry

Gary

Thanks for note. I have read through the post and, unfortunately I am none the wiser. Not very technically minded when it comes to electrics. Do I just need to rewire the trailer plug? If so, how?

Any explicit instructions would be greatly appreciated.

Originally Posted by Graeme

I assume the RRS uses the same wiring as the D3 & D4 whereby the pin that is used for trailer brakes has a 2nd tail-light supply, so when the lights are on, so are the brakes! To make a temporary fix, remove the wire from pin 5 of the trailer plug (its probably blue).

I towed an older pop-top home recently but didn't realize that it has electric brakes, thinking it was too old so didn't look. However there is an electrical fault so they didn't operate when I had the lights on. I haven't fitted my P3 yet so haven't cut the 2nd tail-light supply to the trailer socket.

Originally Posted by Graeme

Left and right tail-lights are provided on separate circuits.

Originally Posted by sniegy

Garry, we cut the wire at the fuse block in the cargo area, this also gives you a connection point for the trailer brake feed wire.
You would of probably noticed that the rear of the trailer plug is solid & filled with silicon so no dirt or water can corrode the connections in the plug.

Lift the lid on the floor cargo area where your tools are & there should be a fuse block located on the lhs, unclip the fuse block & locate the side where the brown & black wire are next to each other, now cut the brown wire 2 inches or so away from the fuse block & solder the brown wire from the fuse block end to the black wire next to it, this will now make 1 park light circuit.
Now the blue wire from the trailer brake unit can connect to the brown wire that runs into the loom.
HTH
Cheers

Here are some of the relevant posts - note what Sniegy has said - the instructions how to fix the rear wiring etc - of course the Auto Elect coukld have wired it up wrong as well.

If it is the above issue, the brakes on the trailer will be on when the car headlights are on.

Now there are also detailed instructions on how to wire the controller in the RRS/D3/D4 section so do a search and you should find it.

Cheers

Garry