Disco 2 LED indicators flashing double speed

So here's one that's got me puzzled:

Just changed over to LED indicators (had to change a couple of worn / intermittent bulbs following MOT so thought I may as well go LED) - proper Halfrauds ones not cheap Chinese Fleabay imports - all works fine, much brighter, but for some reason they flash at twice the speed (as if a bulb had gone). I'm assuming the LEDs have less load than a normal filament bulb (thought they would have been made with an internal resistor to compensate, but I guess not).

I spoke to the chief spotty teenager at the local Halfrauds branch and he just grinned stupidly and mumbled something about not having come across this before - so was as much help as i'd expected.

Ok, so here's the bit where I confess - I only use them because I've got a trade card and at half price on bulbs their prices are actually quite good!

So, whereas i'm happy to leave them as they are, and I've just passed the MOT (would flash speed be an issue??), I feel I should probably comply before Mr Policeman takes offence at my acceptance of the abnormal and writes me a ticket for it (yes, around here they really can be that petty!).

Does anyone know if there's a different flasher unit / relay available that will be a straight swap and compensate? I don't really want to mess about with the wiring just in case I ever want to go back to filament bulbs.

In case it makes a difference, front and rears are now LED but side repeaters have not been changed so are still standard bulbs.

Any thoughts????

I don't quite know what happens in the Disco, not having one myself, but in the defender you need to compensate for the lower current draw of the LED lamps. usually this involves fitting a different flasher control unit/relay. When I got mine I bought an appropriate flasher unit at the same time as the vendor was aware of this problem and had them in stock. In the Defender it's something like this:
http://www.ebay.co.uk/itm/Genuine-W...976365&hash=item43f872698e:g:q0UAAOSw4CFYzXdO
I was trying to find you a Discovery II one, but it's bed time and I'm tired.

OK Paul, there are generally two ways of sorting this problem, and yes you are correct it's down to the lower current being drawn by LEDs.
The first way is to replace the flasher relay with one designed for LEDs, they're fairly easily obtainable on that famous auction site, but I'll have to have a bit of a dig into the diagrams to find out exactly where it is on the car.
The second way and with the facelift Disco the one I think might be easier is to fit a suitable resistor wired across each LED to correct the current being drawn through the flasher relay. There are kits to do this on that same auction site.
If you're like me, you aren't really interested in the reduction in the current being drawn, but more in the reliability and robustness of LEDs over filament bulbs.
The repeater lights on the wings can be changed to LEDs at any time with no modification. I've used yellow LEDs on mine.
I'll get back to you with more information soon.

thanks guys - it's way better than Wikipedia on here!! (Wiki usually gets the answers wrong!!)

Looks like i'll be spending some time in the morning doing an interweb search for the correct LED flasher unit (sounds the easier fix), hopefully Haynes or Google will tell me where the flasher unit is located and it'll be a simple job to swap it over??

Brian, you're quite right, I don't really mind about the minimal difference in power drain from the indicators (I only use them with engine running anyway!) so the choice of LED was partly the brighter light and partly the long life -- anything that cuts down the number of little jobs that have to be done each week is a positive in my book.

My only real concerns are that with them flashing too fast will something go wrong / will they not last as long? And is the a "legal" flash speed (on thing to ask I know but it does seem virtually all vehicles are about the same and i'd have thought that if there was no reason then they'd have all varied depending on brand / type of bulbs, brand of cable, brand of relay, etc.)?

If there's no harm and no reason to conform to the norm, then I might just rebel against the system and leave them as they are!

But for now i'm gonna get some sleep and worry about it in the morning

@Paul Leinichen
OK Paul, I've had a read up on the operation of the hazard/indicator lights on the facelift D2 and you won't be able to use a relay for LEDs, because the timing of the flash rate is done electronically inside the IDM. I've attached the wiring diagram and you can see the indicator switch (bottom right) and if you follow the wires through the BCU they end up at the IDM. That unit is part of the fuse board behind the panel below the steering wheel and quite frankly I wouldn't advise anyone to go in there with a view to modifying it.
As I said, the way to go now would seem to be wiring a big resistor across each bulb holder where a LED is fitted to "kid" the IDM into thinking that a filament bulb is fitted. One downside of this method is that the "fault detection system" won't work unless the resistor goes faulty, but since LEDs are more reliable than filaments that shouldn't be a concern.

https://www.ebay.co.uk/itm/4x-LED-Indicator-50W-6-Flash-Rate-Relay-Turn-Signal-Load-Resistor-Bulbs-Ballast/162337522305?epid=2056370220&hash=item25cc120281:g:mrcAAOSw5cRZFSQq
I believe that the acceptable legal flash rate is between 1 and 2 flashes per second, but these days it's sort of obvious when it's wrong.

I can tell for sure that there's no other way than adding resistors on a D2 if indicator LEDs are fitted which as Brian well observed would ''bypass'' the bulb failure warning too though i disagree that it's not a concern and IMO it doesnt worth the risk to rely on the LED's reliability(which is not 100% what ever you do) so you can provoke an accident by turning one side without knowing that the indicator doesnt work and other participants dont know what you are doing... that risk exists and it's not one to be taken just to save a little money on some bulbs from time to time

i'm wondering what would be the opinion of the insurance company or even the police about those resistors on the indicator circuit in case of an accident ?.

Well done Brian 47. I'd got as far as not finding any flasher units for the Disco II but hadn't dug into why not. Makes me glad I've got a Defender.

You can't just whip out the items entitled 'relay direction indicator' and replace with something more suitable then?

Yes, I think most insurance companies would consider this a notifiable job, because you're not just replacing like with like. I told my insurers, as I'd fitted these and a spare wheel bracket at the same time and I see they've put them down as 'exterior changes' on my documentation. They wanted to put them as 'rally lights', but I insisted that there weren't any additional lights, just a change from filament bulbs to LEDs.

So far, I've replaced most of my lights with LEDs except the headlights, front fogs and spot lights and the indicators.
The headlights, etc. I've left alone because the reflectors and lenses aren't designed to work with LEDs so the beam patterns would be totally screwed up and I've left the indicators with filaments because of the trouble already discussed here, although I did look at doing it some time back.
The lights I have changed very successfully include front side lights, rear stop/tail, high level stop light, rear fogs, reversing lights (with Cree LEDs), direction indicator repeaters and all the internal lighting. I decided to use LEDs of the same colour as the lenses they were working with for two reasons, LEDs tend to have a different colour from filaments, consequently "white" LEDs could distort he original colour of the lens and secondly, if the lens should become damaged, then the light which would show through the damage would still be the proper colour. Since the price difference is little or nothing at all, it seemed a "no-brainer".
When installing LEDs, there's the possibility that the wiring to the bulbholder might have to be changed around to get the LED to work.
The only other minor trouble I encountered was with the high level brake light which started to behave oddly when working with the LEDs in the stop/tail units. I cleared that problem with what's known in the trade as "current steering diodes", in other words, diodes in series with the LEDs to prevent current flowing back through circuitry.
I used CREE LEDs in the reversing lights because to my way of thinking they do two jobs; indicate to other road users that you've engaged reverse gear and secondly to illuminate the area into which you're going to drive. CREE LEDs are very much brighter than ordinary LEDs. The only downside with them is that they do create a bit of radio interference while they're on; a small price to pay.

Hmmmm, in that case I might just take them back to Halfrauds for a refund - they were expensive and clearly are not fit for purpose (I just rechecked the website, put in my vehicle reg. so parts listed are model specific, and it definitely lists these as direct replacement indicator bulbs for front and rear - which clearly they aren't! There's no mention about needing to change flasher unit, fit resistors or do any other mods to be able to use them). Luckily still got boxes and receipt.

The biggest pain in the arse is I don't think I've got enough filament bulbs left to replace them at home, so i'll have to take them out and borrow the missus' car to go down and change them (and then she's gonna moan at me for moving the seat / mirrors / etc. - in fairness she'll probably moan at me about something or other anyway before we ever get as far as discussing the car, i'll do my level best to make sure she does !!).

On the subject of LED lighting though, i'm off to pick up a front winch bumper tomorrow and it's got built in LED fogs. I'm assuming these won't cause any problems (currently have LED bulbs in the rear fogs and they seem fine)??

No, only the indicator LEDs are a problem for the D2

Paul Leinichen said:

Hmmmm, in that case I might just take them back to Halfrauds for a refund - they were expensive and clearly are not fit for purpose (I just rechecked the website, put in my vehicle reg. so parts listed are model specific, and it definitely lists these as direct replacement indicator bulbs for front and rear - which clearly they aren't! There's no mention about needing to change flasher unit, fit resistors or do any other mods to be able to use them). Luckily still got boxes and receipt.

On the subject of LED lighting though, i'm off to pick up a front winch bumper tomorrow and it's got built in LED fogs. I'm assuming these won't cause any problems (currently have LED bulbs in the rear fogs and they seem fine)??

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TBH Paul, the LEDs which you bought are a direct replacement for the bulbs which you removed in as much as they have the correct base, contact positions and voltage rating. Unfortunately the circuit wasn't designed to accept those LED replacements, an odd place to be, but you should be able to get your refund.
Regarding the LED fog lights, if the fog light fittings are designed for LED then you shouldn't have any problems. The trouble occurs when LEDs are fitted into light fittings which were designed for filament bulbs.

As a bit of an aside, I got hold of a small-ish twirly amber light beacon with a magnetic base (yes, the roof of the D2 is steel) just in case it's ever needed should LZIR come calling. Anyway it had a silly little 6 watt bulb in it so I did use one of those "direct replacement for a 21 watt" yellow LEDs in it instead. No trouble with fitting the orange dome, the rotating mirror does its job and being LED there's no heat build-up to damage the plastic dome. Sorted.

Cheers everyone - after a few minutes swapping back to the original bulbs (and a few raised eyebrows from my neighbours who seem to think i'm slightly made for bothering with a Discovery at all as all they see is me doing stuff to it!), it was a trip to Halfords with receipt and screenshot of their website showing i'd searched by reg number and these bulbs were listed specifically as front and rear indicators. Spoke to the "supervisor" (though, to be honest, i'm not sure it he left school much longer ago than I last had a cuppa!) and refund obtained without any trouble. So, credit where it's due, big round of applause to Halfords for problem-free customer service.

I know there are a few other fittings of LED bulbs that are now advertised as "filament" and are supposed to be a direct swap (load and all), so fingers crossed they will be about for the Disco 2 indicators soon. The ones that I used were much brighter and clearer to see so would be great if we could get a set of them that work properly.

So, LED bulbs went back to Halfords - no trouble getting a refund (well done Halfords!) - standard bulbs back in place. Shame really as the LED bulbs were much brighter and significantly more visible (especially in bright sunshine). Hopefully there'll be a similarly bright LED version available soon that's filament bulbs replacement compatible - until then it's standard old, dull, bulbs (but at least they work properly).