LED lights - need resistors

[Huskywatch]

Hi Guys & Gals, Was just hoping someone could give me some advice.. I have only recently acquired my first Range Rover Sport (2008 TDV8) (Very happy with it so far!)... I have a few trailers I will need to tow with it (6x4 Box trailer, Large dog float, and 8m long Caravan). Most of these trailers have LED lights, or soon will have (I bet most of you are already saying "I bet I know the problem!")... Yes you are correct, I am getting the LED indicators on the trailers doing very short flashes every few seconds when connected to the RRS. I have read up on this a fair bit and realize I need to fit load resistors... I have just done this on one of the trailers, and now on the dash when the indicators are active I can see the trailer light flash in time with the indicators, however the trailers indicators still do these short flashes, and I understand that the trailer light should come on when the key is in the ignition and turned to just before turning over the engine, which is not happening..... Am I missing something? I have the resistors between the indicator wire and the earth wire on the trailer on both indicators.

Thanks for any advice you might be able to offer...

I notice that with the resistors installed the reversing sensors are no longer pinging when in reverse, so they are working... just not stopping the flickering...

[p38arover]

Have a look at Lee Bourgeois' range of various Busta units here: Euro (http://www.labtronx.com.au/labtronx-products/euro)

Lee knows Land Rover electronics. His username on this forum is "wires".

[Ferret]

... Am I missing something? I have the resistors between the indicator wire and the earth wire on the trailer on both indicators.

Thanks for any advice you might be able to offer...

I notice that with the resistors installed the reversing sensors are no longer pinging when in reverse, so they are working... just not stopping the flickering...

The presence of a trailer is detected by sending an electrical pulse down the trailer indicator wires. If sufficient resistance is detected during the pulse the vehicle assumes a trailer is connected - hence the need for fitting resistors. However, fitting the resistors does not stop the vehicle from pulsing the indicators wires.

You need something in addition to the resistors to stop the constant electrical pulsing reaching the trailer indicators. Earlier models, like yours, pulsed continuously even after a trailer was initially detected - so the indicators flash. Later models only pulsed once to detect a trailer - so don't have the flashing problem and therefore only need resistors fitted.

[Grappler]

To overcome the rapid pulsing i used a pair relays on the indicator circuits as well as the dummy resistors
I put up a post with picture of the circuit in the old aulro that i cant find now

[Davidno64]

Hi Guys & Gals, Was just hoping someone could give me some advice..... Yes you are correct, I am getting the LED indicators on the trailers doing very short flashes every few seconds when connected to the RRS. I have read up on this a fair bit and realize I need to fit load resistors........ Am I missing something? I have the resistors between the indicator wire and the earth wire on the trailer on both indicators.

Thanks for any advice you might be able to offer...

I notice that with the resistors installed the reversing sensors are no longer pinging when in reverse, so they are working... just not stopping the flickering...


You have another option. Keep you're LED lights as they are. Usually the load resistors are for LED's and Current Sensing. Where cars use variations of Current Sensing, to test for blown globes. (Usually sending a small AC Signal thorough the lighting system and monitoring it. And computer turning on a warning light, telling of a blown globe). ...change the Flasher Can in you're car to a newer type (LED compatible).

This will allow you're car to operate as normal, trailers added to the load LED or Globe to have minmal loading. Not affecting Flash rate. If using a quality item, now indicators will flash at a set rate irrespective of load or Globe Type. Problem solved for-ever. ((WHAT: standard Flasher Cans are load sensitive. Purpose was it was the Teck of the day and also if a Globe blew. Less load on the system and the Flash rate would increase, warning of blown globe.
The system needed a set resistance, meaning a set wattage for each Globe. It you changed the wattage of any indicator globe (or substituted LED). Then Indicator Flash rate would increase)).

Latter design (and specific) Flasher Cans, of electronic variety's, not old style relay based Flasher cans. Are not load based, the Flash rate is electronically (not electrically) controlled. Giving a set Flash rate, irrespective of Globe Type. (Do not be fooled by imitation Flasher Cans, that are really older design but re-calibrated for LED's.). Fully Electronic and non-load sensing......I have one fitted to my Motorcycle. Globes, LED's or no Globes will flash the indicator/idiot lights at a set rate, irrespective. Bought years ago, I think from Jaycar Electronics?

[87County]

I hope this helps :)


Flasher Relays - LED | Tridon (http://www.tridon.com.au/products/Tridon/35/478/flashers-and-relays/104173/flasher-relays-led)

Flasher Relays - Electro Mechanical | Tridon (http://www.tridon.com.au/products/Tridon/35/478/flashers-and-relays/104171/flasher-relays-electro-mechanical)

[p38arover]

Do late model cars, esp. LR, use flasher cans?

On my P38A and, I think, the L322 (I haven't looked yet), the flash control was by an ECU. That gives them a lot more "smarts", e.g., maintaining the correct flash rate at the indicators themselves but double flashing on the binnacle warning light, etc.

EDIT: I just checked the L322 wiring diagram, there is no flasher can. It looks like it is controlled from the LCM (Light Check Module) which handles indicators and other exterior lights.


General
The exterior lighting is controlled by the Light Check Module (LCM). The LCM controls the following vehicle functions:
l Control and monitoring of exterior lamps including direction indicators and hazard warning functionality
l Illumination dimmer control of instrument pack and all interior switch illumination
l Communication and control and monitoring of trailer lighting via the trailer ECU
l Control of power supply to automatic headlamp headlamp levelling ECU (only with bi-xenon headlamps option)
l Monitoring and evaluation of check control inputs from other system ECU's and output of applicable messages
in the instrument pack message centre.
The LCM is connected to the I Bus and communicates with other vehicle systems via the instrument pack. The LCM
contains a microprocessor which performs the control, monitoring and evaluation functions.

I'd suggest the L320 is the similar.

[Grappler]

The rapid pulsing of the trailer leds is the vehicle system sensing if a trailer is attached. When a trailer is detected the reverse sensor is deactivated and some traction/stability and EAS functions are limited
The rapid pulsing of the trailer leds occurs even when the indicator flashers are not activated.

[Challenged]

The rapid pulsing of the trailer leds is the vehicle system sensing if a trailer is attached. When a trailer is detected the reverse sensor is deactivated and some traction/stability and EAS functions are limited
The rapid pulsing of the trailer leds occurs even when the indicator flashers are not activated.
This happens even with the load resistors connected and the trailer icon on the dash illuminating so the car is detecting the trailer, does anyone know how to stop the unwanted flashing of the indicators other than going back to incandescent globes?

[bee utey]

This happens even with the load resistors connected and the trailer icon on the dash illuminating so the car is detecting the trailer, does anyone know how to stop the unwanted flashing of the indicators other than going back to incandescent globes?

Relays fitted to the trailer plug wires or a dedicated towing module. Example:

Trailer Towing Modules (https://www.gore-research.com.au/trailer-towing-adaptor-modules.html)

[Challenged]

[bigsmile1] got it sorted with help from the Disco forum, fitted a pair of relays into the indicator feed to put a physical break in the circuit so the pulse can't get to the LEDs

Made one to permanently mount in the camper and need a second portable one for other trailers, easy to make, used the Narva type dummy load resistors and a couple of Bosch mini relays I had floating around.

145258

[Grappler]

This happens even with the load resistors connected and the trailer icon on the dash illuminating so the car is detecting the trailer, does anyone know how to stop the unwanted flashing of the indicators other than going back to incandescent globes?

This is the design by Colin Pederson, from 2010, I also used the design to build a box to eliminate both the non recognition of the trailer leds and the flashing problem. I put it in a box with whips and a socket so I can use it on any led trailer. The dummy resistors allows recognition of the trailer attached and the relays defeat the flashing

https://www.aulro.com/afvb/attachments/the-d3-d4-sticky-zone/28894d1284699029-discovery-3-led-trailer-lights-disco-3-led-light-diagram.pdf