KISSMYAURA said:

Why fit load resistors they defeat the whole object of less power. ?

A Standard Flasher Relay works on load, this means it is designed to see 21 watts bulbs, when you fit LED lamps or bulbs the Relay can not detect the load as the LED lamp/LED bulb may only use 2 to 3 watts, resulting in fast flashing which is no good to anyone. (WICRAP)

So people fitted load resistors to imitate the load of the incandescent bulbs they have just removed, resulting in more wiring, things that get hot, melt anything near them and the best bit you are using more power than a standard bulb set up!

Then came LED Flasher Relays

These often only could handle 30 to 40 watts which is fine for all LED vehicles but as soon as you put a trailer on it would blow or the user would fit the relay with bulbs and blow the LED Flasher Relay.

Some have tried to create a 4 Pin Flasher Relay but they state it might put the trailer light on when you are not pulling a trailer plus it can only handle 40 watts rdx relay can handle 140 watts.

WIPAC attempted to copy RDX Relay but failed all they could do was adjust the flash rate, it puts the trailer light on when you are not even pulling a trailer.

RDX 4 Pin Flasher Relay can handle bulbs, LEDs and a mixture of both on the vehicle.

Tuneable this means it can be adjusted to suit your vehicle by simply turning the adjustment knob on top of the RDX 4 Pin Flasher Relay.

MOT law changed resulting in the trailer light must flash when a trailer is connected and the indicators/hazard is used. The MOT station can now test the towing socket if fitted!

Other Flasher Relays including the WIPAC LED Flasher Relay cannot detect a trailer has been connected which is now a requirement.

The trailer must be using incandescent bulbs or LED lamps with load resistors for the Trailer light to flash. It cannot detect trailers solely on LED lamps it will make them flash ok but will not flash the trailer light as the extra load is too little to detect.

You pays yer money you takes yer choice!

Its not often something just works and does what it should, I am very happy with it.

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brian47 said:

There are some flasher circuits such as that in the Discovery 2 where the flash rate is actually set by electronic components which drive the appropriate relays instead of the thermally calibrated type in older vehicles. There's no way to fit such a "LED relay".

Whilst the thread starter placed this in general is about Defender LED conversions ( see first post)


The 13 way towing socket is part of the MoT, the 7 way 12N type isn't.

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Discokids said:

That all makes sense but imo nobody in the history of anything anywhere ever said they're fitting LED's to save power. People fit them because they look better, fresher and brighter.
Meaning that to avoid changing relays or having to faff about when you hitch up, load resistors do have a place, even if technically it isn't best practice.

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