Discovery 4 - Trailer LED Tail Light Pulse

[HI_SAILOR50]

Hi. Not sure if this has been addressed previously .... I recently purchased a second hand D4 2015 and have a caravan with LED taillights. I have noticed that the trailer icon dose not illuminate in the dash when I connect up and the reversing proximity tone sounds when I am reversing with Van connected. I have read on other forums that European cars don't recognize that you have trailer on as the resistance in the LED bulbs is less than iof you had incandescent taillghts on the van. While we don't have flickering taillights on the van, the fact that the car doesn't recognize a trailer is attached means that the towing safety / engine features are not active (and the reversing tone adds to the stress of backing the van). Have I been misled, is it a thing? and what advice might you all have regards a remedy ?

[DiscoJeffster]

Hi. Not sure if this has been addressed previously



Lol. You’ve clearly not done a search here, or read the FAQ. Everything you need is on the forum, addressed hundreds of times.

[HI_SAILOR50]

Lol. You’ve clearly not done a search here, or read the FAQ. Everything you need is on the forum, addressed hundreds of times.

Hi - new to the forum and not found it easy to navigate. Many thanks for your supportive response.

[loanrangie]

Hi - new to the forum and not found it easy to navigate. Many thanks for your supporting response.

If you look up the top there is a stickies section, you'll find all you need to know in there.

[Tombie]

Welcome

Please understand some of us older members have seen the same questions over and over so can get a bit frustrated.

Best search function is actually at the lower left of the page - right down the bottom. It will help you immensely.


In answer to your question: You will need to fit resistors to the indicator circuit.
There are options for this (i'll go with the "paired" solutions which sorts the trailer indication for both sides (as I like the symmetry and its cheap)

You can:
1) Fit 2 resistors to the vans indicator circuits - they remain on the van and only help with towing the van.
2) You can make a box to go between the socket on the D4 and the Van Plug. This is easy to do if you have basic skills. It also allows you to use it with other trailers you may tow
3) You can make a switched box up, that wires inside the vehicle. When you attach a trailer you just flick a switch to turn the box on - allows any trailer to be used

Heres a link on the forum to get you started

Discovery 4 LED trailer lights (https://www.aulro.com/afvb/l319-discovery-3-and-4-a/282788-discovery-4-led-trailer-lights.html)

[p38arover]

Hi - new to the forum and not found it easy to navigate. Many thanks for your supporting response.

The best search engine is Google. Forum search engines are pretty basic.

Try something like this: LED trailer lights Discovery 4 site:aulro.com

Edit the search criteria as needed.


I have read on other forums that European cars don't recognize that you have trailer on as the resistance in the LED bulbs is less than if you had incandescent taillghts on the van.

Not quite right. LEDs draw less current than incandescent lights. Lower resistance results in higher current.

[HI_SAILOR50]

Many thanks. Good guidance.

[Tankmat]

Here’s another thread worth reading

D4 trailer / caravan lights
D4 trailer / caravan lights (https://www.aulro.com/afvb/l319-discovery-3-and-4-a/287645-d4-trailer-caravan-lights.html)