Thread: D4 Electric Trailer Brake Wiring

Originally Posted by Nod

I would have loved to find a "pretty" DPST switch... however never found one.... lots of SPST though!

how about these?
DC 24V 18mm Blue LED Light 22mm Mounted Thread 6 Pin Latching Push Button Switch | eBay
DC 12V 18mm Green LED Light 22mm Mounted Thread DPST Latching Push Button Switch

Originally Posted by Nod

I would have loved to find a "pretty" DPST switch... however never found one.... lots of SPST though!

I didn't give the application a thought...

Hi guys,

I have just installed my TowPro. Very cheap too. Very happy although I did have to order a bag of clips off fleebay. Also very cheap wish i didnt mess round with them so much now i know how cheap they are.

The whole job took me way to long but very happy with install, I installed a switch for trailer blinkers as per NOD, (So now I have a LED module used twice for sale once I read the for sale section rules). I left my switch inside the rear panel until the kids are grown up.
While in there I mounted a relay and picked up a reverse supply to power my reverse cam and reverse spotlight, I also ran another wire from the relay into the 7 pin auxilary/reverse circuit for backing up my boat trailer.

I went a different option under the bonnet and made a stainless plate to mount to the traxide spare battery tray and mounted a marine 50amp CB for my front and rear andersons and also mount my accessorie 30amp cb and trailer brake 25amp cb.

For pretty switches Ashdowns do a few but i like the simple chrome toggle switch with a waterproof cover on it to make it al black and blend into interior.

My LR dealer told me not to connect to the stop lights in my 2012 D4 as resistance can be a problem, which I have found out twice. Connect to the brake switch. Also with the electric brakes fitted, this eliminates the need for any special adaptors if your trailer/caravan has LED lights. This was after buying a compatible $45 adaptor from Ford.

Originally Posted by Discodougie

My LR dealer told me not to connect to the stop lights in my 2012 D4 as resistance can be a problem, which I have found out twice. Connect to the brake switch. Also with the electric brakes fitted, this eliminates the need for any special adaptors if your trailer/caravan has LED lights. This was after buying a compatible $45 adaptor from Ford.

Incorrect the car doesn't know you fitted electric brakes. Also the resistance won't be an issue as the brake controller is on the other side of the diode and has a very low current draw. Led tail lights are not measured through the car the draw is too low. Does the 45 buck adapter bring on the trailer icon on your dash when the blinkers are on. Sounds too cheap may just be a 7 pin large to 7 pin flat adapter at that price.

Everyone on here that has followed sneigys post is trouble free don't trust the dealer

So I wired up my 2012 D4 with a tow pro incorrectly.
The lights come on the trailer, and indicators etc work perfectly.

It is just that the trailer brakes don't seem to come on as I brake, however they do come on if I put on the lights or parkers.

I connected the Blue tow prow wire to the brown Disco wire after the splice and then connected the red wire to the red wire that is in the same loom as the brown wire.

What have I connected incorrectly, I seem to have gone wrong even though I downloaded the very instructional PDF in this thread.

Originally Posted by onesilop

So I wired up my 2012 D4 with a tow pro incorrectly.
The lights come on the trailer, and indicators etc work perfectly.

It is just that the trailer brakes don't seem to come on as I brake, however they do come on if I put on the lights or parkers.

I connected the Blue tow prow wire to the brown Disco wire after the splice and then connected the red wire to the red wire that is in the same loom as the brown wire.

What have I connected incorrectly, I seem to have gone wrong even though I downloaded the very instructional PDF in this thread.

Sounds like the brown wire has not been cut as shown in the wiring diagram on the last page of the pdf?

Scott

Originally Posted by LRD414

Sounds like the brown wire has not been cut as shown in the wiring diagram on the last page of the pdf?

Scott

As I read through the thread again, I started to come the same conclusion.
I didn't cut it but rather spliced in as that is what I thought was called for. I will have to cut and retest. Thanks for the help I will report back when I get a chance to do just that.