Thread: D4 Electric Trailer Brake Wiring

Hi, sorry for a delayed response but I have been off the forum for a while. Yes I have towed with it like that. Including into Dalhousie springs and it works just fine.

Will, John and sniegy, thanks for your advice.
I already had the LED Module but I didn’t like it, or the extra cable length, being zipped tied to the front of the van which is why I wanted to hard wire it into the car.
I’ve now done this running all 7 wires thru the module which I mounted under the car above the spare wheel. It could not be mounted in the L/H storage section, as sniegy's good suggestion, as I’ve already modified and filled up that space with an aux battery, DC-DC charger and 350W inverter.
However, now having 20:20 hindsight I realise that I only needed to run the two turn indicator wires and the earth thru the module. Taking sniegy’s advise I installed an off/on switch on the earth wire and mounted it on top of the trailer plug for easy access .
All good so far but I still need to install the diode so its back under the car again

Hi sniegy,

i have tried to send you a PM, but not sure if you received it as it doesn't show in my sent box

I have put together a doc of all the relevant posts so that I can follow this easily in the garage (without internet connection). Can i forward to you to check? It can then be uploaded onto the thread.

cheers

Simon

First post so please go easy.

I picked up my Disco 4 SE last week and had my electric brake controller fitted today and the large 7 pin plug replaced and wired for a 12 pin for towing my Jayco, which has the Led lights. I plugged the caravan into the socket this evening.

Brakes worked, all the lights worked. Did not notice pulsing. The reversing sensors stopped working and did not start again until I had unplugged the van and turned the car on and off again. However when selecting the indicators or hazards I did not get any symbology on the dashboard.

I have not had any resistors fitted the indicators on the van.

Given that my reversing sensors stopped working, does this mean that the car is recognising the caravan?

Ashhill
Had exactly the same scenario with my disco 4 SE and my jayco van.
We towed around Tasmania for 5000 KM without the trailer indicator light flashing.
We had the electric brakes stop working twice but i beleive that was for another reason since rectified.
Since we came home i bought a pulse busta and have mde it a patch lead, male one end and female the other so i can use depending on the trailer.
I highly reckomend having a good look through this thread and others as there is a lot of information and solutions from people who are a lot more educated in this are than me.
I think then you will be able to make the best solution that fits your neads.
Cheers
Willl
Ps. I now have the trailer light flashing when towing LED trailers but i can't say i've noticed anything different

I have an my12 d4 also and experience the same as above with no flashing trailer light when indicators operate. Reverse sensor stops when led trailer connected. note after connecting I do have to turn car off and on to detect trailer.

Have connected older style trailor with normal globes and same results.

I have had trailer stability assist operate on 2 occasions.

All good :-)

In addition. The newer d4s have led indicator lights anyway don't they?

Have they LR fixed or changed pulse buster requirement?

I have a 2012 D4 3.0L And I tow a caravan and boat that both have Led lights. The lights on them would not pulse or flicker as previously stated with the d4 but I wanted the little green trailer icon on the dash and reverse beeps to disable. I used Led resistors from LED autolamps at $20 for a pair, wired them into the indicator circuits and one in the brake circuit for good luck. I then added a switch to turn these on or off. When turned on I get the trailer icon flashing on every indicator pulse and the reverse beeps are disabled. This was a very easy and inexpensive solution. I also use the tekonsha P3 as my brake controller and it is wired in a per previous posts....